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Interview of Gerald Pearson by Lillian Hoddeson on 1976 August 23, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4812
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Early influences and education; A.B. from Willamette University in physics and math, 1926; fellowship and M.A. from Stanford University; graduate study at Columbia University on x-rays. Work at Bell Laboratories, starting 1929, on vacuum tube amplifiers with John B. Johnson; carbon microphones, semiconductors and the solar battery; work atmosphere and supervisors, Peter J. W. Debye; technical colloquia. History of “thermistors” and transistors. First color TV demonstration. Work during World War II on bombing using radar techniques and infrared. Organization of the Morgan-Shockley solid state group, 1946; appointment as department head at Bell Labs; academic appointment at Stanford University. Also prominently mentioned are: Joseph A. Becker, Hendrik Wade Bode, Walter Houser Brattain, Oliver E. Buckley, Chapin, Carl Christensen, Karl Kelchner Darrow, Clinton Joseph Davisson, Henry Eyring, James Brown Fisk, Harvey Fletcher, Gaylon T. Ford, Lester Halbert Germer, Gibney, Frederick Goucher, H. E. Ives, Frank Jewett, Mervin J. Kelly, Jack Morton, Foster Cary Nix, Ogg, Russell S. Ohl, Arnold Johannes Wilhelm Sommerfeld, Morris Tanenbaum, Gordon K. Teal, Russell Harrison Varian, Oliver Weisner, Dean E. Wooldridge; Pacific Academy in Newberg, and Stanford Solid State Industrial Affiliates.
Before zeroing in on the period of the 30's and 40's, I would like to ask you a few questions about your early background. I see that you are a native of the Northwest that you were born in Salem, Oregon in 1905. Were your parents from Oregon, too?
They came to Oregon from Indiana in 1898.
They were both Americans?
Oh, yes. In fact, we have a record of our ancestors back to England. We have the complete genealogy for eleven generations dating back to 1625.
Well, why don't you give me a brief summary? What I'm most interested in, of course, is the general trends, and where your scientific interests may have come from.
All of my forefathers were farmers. I was the first scientist as far as I know.
What kind of farmers?
My father had a fruit ranch in Oregon and his father had a — well, general farming in Indiana and Ohio.
Was your mother trained in any way?
I might say that my father first — schooling wasn't as easy in those days as it is now and I think he went to what was called a spelling school, which would correspond to having gone through the fourth grade or something like that in the present school system. My mother went through what would correspond to a high school. But they were very insistent that their — I have two brothers — children all go to college and we did.
Are your brothers older or younger?
I have one brother that is older. He has a Ph.D. in theology. He is a Quaker minister. My younger brother obtained a BS in Forestry, and he is a State Forester in the state of Oregon.
Bozorth came from Salem, Oregon, too. Did you know that?
Yes, but I thought it was Portland.
By the way, his wife is a daughter of a former governor of Oregon.
I didn't know that. Do you recall any specific memories from childhood that you believe contributed significantly to your scientific direction — automobiles, telegraphs, radios, batteries, anything before you went to high school?
We didn't have automobiles in those days. I rode a horse. We had a horse and buggy for family transportation. I have always attributed my interest in science to my secondary school science teacher. I didn't go to a public high school but to a private academy instead.
The Pacific Academy in Newberg, Oregon?
Yes, that is a Quaker school. All of my forefathers were Quakers. A teacher at the Academy, Oliver Wiesner taught mathematics and physics. I have often said that he was the guiding light to getting me started in science.
What was your relation to him like?
He was a quiet sort of a fellow, but a very good teacher.
Do you remember any specific incidents, if he said something or showed you something?
Nothing in particular. He was a very inspiring teacher.
What brought you to the Pacific Academy?
As I said, it was a Quaker school and my parents thought it was better than the public schools. So, I have not been in a public school since the eighth grade.
I gather they supported you through this academy.
Were there extracurricular activities in high school that involved you in scientific activities beyond those in your classes?
I don't think so. Well I remember a class in botany. We made a terrarium and this and that.
How did you happen to go to Willamette University?
It is the home town university in Salem. By the way, it’s Willamette. (Heavy accent on am.)
As a friend of mine used to say, the way to remember the pronunciation is it rhymes with damn it. Money was rather scarce and my father needed help on the farm so I first went to Pacific College, which is the college part of Pacific Academy, for one semester. Then things got tight on the farm, so he asked me to come home and help there and go to Willamette, and I lived at home. Our farm was seven miles from Salem.
I see. You entered in around 1922 I guess because your B.A. is 1926. What did you major in?
When I went to Willamette I thought I was going to major in physics and then ah....
Was that a result of Wiesner?
Yes, and then the physics professor at Willamette wasn't just the best, so I decided to major in mathematics. The mathematics professor there was a very competent fellow. The first year I was a physics major and the second year I was a mathematics major and then at the start of the third year I concluded that I wanted to be a physicist regardless of the professor, so I ended by having a complete major in both mathematics and physics.
I guess that then you took a completely science mathematics program.
Well this was a liberal arts college...
You must have taken a little bit of literature and language and whatever. But there wasn't too much time left, I imagine, with a full physics major and a full mathematics major.
I had four years of English I remember. I wasn't too good in English. I remember taking what they called advanced composition. I took that because I thought I wanted to go to graduate school and be able to write a thesis. Even though I was poor in English, I took it anyway. By the way, the term paper which was 50,000 words was on the History of Science.
Do you remember on which subject?
It leaned towards physics.
So you were already prepared to go to graduate school, or at least you were thinking about it. Any summer jobs at that time?
Always on my father's farm.
Did your father support you at Willamette?
Of course, there wasn't any board and room since I stayed at home. I borrowed money for the tuition. He couldn't support me with that, although the tuition was very low at that time. The first year after I graduated I taught high school to pay off my bills.
Before we leave Willamette, I want to ask you a little bit more about what the physics was that you learned there. This was 1922-1926. Were you aware of quantum mechanics that was being developed at that time?
The first good book on quantum mechanics didn't come out until I was a graduate student at Stanford, about 1927 or 1928.
Which one are you referring to?
You are not referring to Atombau and Spektrallinien?
You probably know more about this than I do. I remember that at Stanford we were getting headaches. It was a book on quantum mechanics which we used in a course. It was in German and each one of us had to translate a chapter or so.
It could have been a Sommerfeld book. His famous book was earlier, it was on the old quantum theory. But then he wrote others later and it is interesting that they were using it at Stanford. Well then I gather you did learn something about atomic physics but, you probably weren't learning very much about quantum mechanics in that period as an undergraduate in college.
No. The physics professor was an electrical engineer of the old school, and it was mainly fundamentals. The text book which I remember was half engineering and half physics. By the way, at Willamette they always chose the best student to be what they called the senior scholar, and he helped in the physics laboratory courses. I was the senior scholar in physics.
I see, so you spent a lot of time in the laboratory. Was that your first experience in laboratory work?
Yes, although we did some elementary experiments at Pacific Academy.
You didn't have much time at home I guess because you were busy working on the farm.
By then we had cars. There was no electricity, but my father bought a home electric generator and we had radios. I made my own.
Alright, then you spent a year in Umapine High School, in Oregon earning some money to pay off your debts.
That is right.
What did you teach there?
There was a little booklet put out by the state of Oregon that gave the salary of every teacher. The ones that were way out in the sticks had the highest salary. So I looked in the book for the highest salary and applied and got the job. There were only 30 students in the school. There were three teachers, and so each taught a lot of courses. I taught the mathematics courses and of course I taught the physics course and I also taught World History and Civics and I was the coach of the baseball team and the basketball team. My wife likes to remind people that my boys' basketball team didn't win a game all year, but the girls' won every one.
When did you make the decision to go to Stanford?
I applied for and got a fellowship. I was offered the principalship at the high school the following year.
Did that tempt you?
No, I obtained this fellowship from Stanford. When I was in college I always said I wanted to go to graduate school. I either wanted to go to Columbia or the University of Chicago or Stanford. I was happy when I received the Stanford fellowship.
I see; did you apply to the other two schools?
No, but I did go to Columbia later on.
Yes, we will get to that in '29 or '30. O.k. so you applied and you got there and spent two years there.
I'd like to know what you focused on there. What courses you took, who some of your teachers were and some of your fellow students?
In those days you had to do research to get a masters' degree and write a thesis. The head of the department was David Webster.
Physics. My research director was P.A. Ross, and the big push in those days at Stanford was X-rays, so my research was on X-rays.
Was it entirely an experimental thesis?
No. I have a copy of it right here.
Wonderful. We will look at it while we are talking: "Relative Probabilities of the Ionization of K and L Electrons of Equal Ionization Energy."
That was published, by the way, in the Proceedings of the National Academy of Sciences...
Volume 15, No. 8, pages 656-664 (1929).
You see the ionization energies of the L electrons of one of the elements are close to the K ionization energy of the other element. So you have nearly equal wavelengths... here are the selenium L lines and here the lead K lines, and they are right along there, and from the relative intensities one can calculate the relative probability of ionization. So the thesis wasn't all experimental, it had a few fancy equations in it.
(glancing through thesis) Duane was at Harvard.
Yes, Duane was Webster's mentor. Webster came to Stanford from Harvard.
Oh, I see, he was Duane's student. You see, this is one of the things you must save with your papers, that I hope one day will be accessible to scholars. Were there other outstanding teachers who played a significant role in your career at that time besides Webster at Stanford? This was of course before Stanford began building up so tremendously.
Yes, this was when they were poorer. All the equipment was homemade. We had a glassblower and we made our own X-ray tubes, our own targets and put the X-ray tube on a pump which ran continuously to evacuate it. It wasn't sealed off. Well, another professor I remember very vividly was George Harrison. He was a spectroscopy man at Stanford. And he later went to MIT. He's returned now. Webster, by the way is 90 some years old. He's still living here in Palo Alto. I see him once in a while.
I remember other professors, but they were more... these were the research people, Harrison and Webster and Ross. You know W. W. Hansen? He married Ross' daughter. Bill Hansen and Russell Varian were my classmates. We worked side by side on our research. My first oral paper presented at the American Physical Society was a joint one with Bill Hansen.
That was not a publication.
No, that was not a publication. It was an oral presentation. I have a complete list of those over there too, if you want to see them.
I'd love to see those later too. Well now, just before we leave Stanford. The quantum mechanics there you say was taught out of the Sommerfeld book and Webster taught it.
I remember it was very tough because I wasn't theoretically inclined nor a very good German student. I had taken French as an undergraduate and in those days you had to pass two language tests for your Master's degree. No, you had to pass one and two for your doctorate. So I was studying German to get ready for my second language. But I used the dictionary more than anything else to translate.
That's ok for reading scientific papers.
Each summer Stanford had a visiting professor which they brought in. I remember the first summer I was there it was K. K. Darrow from Bell Labs. The course was on modern physics. You have undoubtedly have heard of K. K. Darrow.
He hadn't yet written most of his famous articles for the Bell System Technical Journal at that time.
He hadn't published the book yet.
This was then the book that was based on those articles?
Yes. And then the second year the visiting professor was J. H. Van Vleck from Harvard.
And what did he talk about?
The course was always called modern physics. I remember that I wrote a term paper on isotopes, where magnetic fields were used to separate them, and so forth. I still have that term paper at home. Van Vleck said it was very good.
Do save it. It's important for historians. Ok, so you came into contact with modern physics through Darrow and Van Vleck. That's very interesting. When and from where did you first hear about the Bell Laboratories?
Well, as I say, Darrow of Bell Laboratories was the visiting professor the first summer I was here.
Was that '27 or so?
Yes, '27. He was the professor in the summer of '27; Van Vleck in summer of '28. I left in June '29.
So you heard about Bell Laboratories from Darrow. What led you to apply or did someone come along and recruit you?
I didn't apply. The recruiter visited the Stanford campus.
Do you remember who came?
Oh, I should, but I don't. He was head of the personnel department.
Prior to Long. He lives near Berkeley, now. I can't come up with his name right now. He visited the campus, and then arrangements were made to talk to him. I remember Russell Varian and I went over together. Russell wanted in the worst way to go to Bell Labs and I was curious. I don't know whether you know that Russell Varian wasn't the best academically.
I don't know much about that at all.
He was not given an offer, and I was which he thought was terrible. I told him later that if he'd gone to Bell Laboratories, his career might not have been anything like it was. He wouldn't have invented the klystron and started his own company and become a millionaire.
I don't know of any millionaires at Bell Labs. You don't become a millionaire on a salary. He'd have to have left to form his company.
You sell your patent rights, don't you, immediately when you join Bell Labs?
Yes, for a dollar.
For a dollar. And that keeps you from becoming a millionaire. What were your expectations before you actually went to Bell Laboratories?
I was given three offers at that time. By the way, this was 1929, you know, just prior...
Just before the Depression. But people were hiring like mad then.
Yes, I was given this offer at Bell Laboratories. The other two were teaching positions, one at the University of Hawaii and the other at the University of Arizona.
Hawaii? Had you applied for those?
Yes, I had applied.
But not for the Bell Laboratories one.
No. There was a professor at Stanford, Kilpatrick, who spent part-time as a professor at Hawaii. They were both higher salaries than Bell Laboratories. And I remember one of the professors here, a visiting professor here, who had lived in New York, said I couldn't possibly live in New York on the salary they offered, and he advised me to take a teaching position. But I didn't.
How did you decide to go to Bell?
Those were in the days of Davisson and Germer and I think everybody wanted... well if you wanted to be somebody, you wanted to work at Bell Labs.
I didn't realize that Bell was that well known in '29.
Not as well-known as it was later, but the Davisson and Germer experiments were in all the newspapers and in science journals. They hadn't received the Nobel Prize yet, but...
I didn't realize the experiments were that well-advertised. They certainly deserved to be.
It was in the physics journals.
Then you moved to New York.
I went home to Oregon and got married first.
So then you and your wife moved to New York, and where did you live?
The first year we lived in the Bronx. As I say, the starting salary for a Master's degree was $36 a week. So you didn't choose your spots.
So you lived in the Bronx and you commuted down.
On the elevated.
And you worked at West Street. Now, the first bit of research that you got involved with at the Laboratories was on noise in vacuum tube amplifiers.
And you worked under J. B. Johnson.
And continued to until 1938.
When I first reported at Bell Labs, Johnson was on a visit to Sweden. He didn't come back for a month or so after I arrived. But it was decided that I should work for him even though he was away.
Who decided, do you know?
Oliver Buckley at that time was the Assistant Director of Research and Johnson reported to him. When I first arrived they had a week of lectures to orient us. I still have a picture at home of all the people that were in that course.
I'd be very interested in looking at that some time.
I don't remember the specifics of how it came to be Johnson. He isn't on this list.
Well, that's because you were then in a special research department and he was in physical research.
But we were in there also.
There was a division for a while, in the late '20s, between this special research department which was under Buckley and the physical research department. Later they put them together.
Buckley then went up as President and Fletcher took over. I remember that the month before Johnson came back Fredrick Goucher was sort of my mentor.
I'd be interested in your recollections of Goucher.
I can tell you lots of things about him.
In what connection did you associate with him?
He was a graduate of Columbia. And he worked on photo emission. But when he came to Bell Labs, he worked on carbon. And for many years he was trying to make a synthetic material… synthetic carbon to replace the natural carbon granules in the telephone set. That was his main job. He was working on the physics of carbon particles in the telephone transmitter. In fact, in the newspaper (refers to paper) you see here, Carl Christensen worked for Goucher and we worked together and published this paper on noise in the carbon microphone.
This is one of the ones I happen to have with me. This is a 1936 paper. You and Christensen were on the same level and so I gather there was some interaction between Goucher's group and Johnson's group.
Yes, Dick Haynes was also a member of this group. I was an usher at his wedding.
Did you all work in the same laboratory?
In adjoining rooms.
Did you know about each other's work in detail.
Did you spend part of your work day discussing each other's problems.
We usually went to lunch together.
And then I suppose you'd talk shop often at lunch. I see.
Could you tell me something about Christensen, too. I know very little about him.
Carl Christensen was from California. He got his Ph.D. at Berkeley. He had a Ph.D. and I had an MA. This is 1930. You see, I arrived at Bell Labs in September 1, 1929.
Was it your impression then that most of the people had Ph.D.'s?
Well, let's see. No one in this group had a Ph.D.
No one under Johnson or Weinhart.
Weinhart didn't. Bozarth had a Ph.D., Cioffi did not and Elwood did. Haworth did not. Christensen did. Haynes did not. I would say that not more than 10 or 15% had Ph.D.'s in those days. Curtis didn't have a Ph.D. I don't know about Elman but I would doubt it.
Did you interact much with Bozarth in those days?
In what way?
We were all on the same floor at West Street. He was more on research in magnetics and Elman was more on the technology of magnetics.
But you weren't really working on magnetics much, you were working on noise.
Well, there is noise in magnetic materials too. Let's see what you do call it when the little magnetic poles slip over... it's been so many years since I've thought of these things I can't come up with a name. Oh yes, the Barkhausen Effect. But if you have a magnetic bar and you have a pickup and then you bring a magnet up and twist it over, you can hear each individual magnetic domain flip. I was studying shot noise and thermal noise and I remember we had a demonstration for the visitors that came through the laboratories. And we added the Barkhausen Effect also — If you put a couple of electrodes in your arm and then you tense your muscles, you also get a noise — I had that demonstration also.
Did you know Nyquist?
Oh yes. You see, Johnson and Nyquist worked together.
Nyquist is not on these charts.
No, he was down at AT&T. Just a couple of years before I went back there, Johnson discovered thermal noise, which is sometimes called Johnson noise now. And Nyquist is the man who did the theoretical analysis of this effect. So Nyquist and Johnson were very good friends. We used to play bridge with the Johnsons and the Nyquists.
And Johnson continued to work on noise for many many years after that.
Of course that is not the only thing he worked on. He made early cathode rays tube also.
What was it like to work under Johnson?
Well, I always said he was the nicest boss I ever had at Bell Labs. He wasn't as keen a scientist as some of them, but he was a real gentlemen. I always said the smartest boss I ever had at the Laboratories was Wooldridge, Dean Wooldridge. Then there were several others, too.
Did Johnson direct you much? I'm trying to get a feeling for what it was like to be a researcher at Bell Laboratories in those days.
No, well he helped me a great deal, but it was mainly that I would go into his office and ask for help.
So he posed the problem, and left you alone with it?
Yes. Speaking of that, I was always in the physical research department, and I remember that we had an annual survey where you spoke to the big boss — I still remember a good number of years that I have that report to Fletcher — and all of my associates were there. When I finished I'd always ask Harvey Fletcher, "What do you think — how should my work be directed in the coming year?" And he always had a stock answer, "You're much better able to determine that than I am." So as long as you did good work and in an area of interest of the Bell System, you were left alone in the Research Department.
Did you always feel this.
Under every boss that you had? Did Buckley ever interject his ideas of what should be done?
No, the only one who injected was Kelly. Buckley didn't inject so much. I remember one thing. Buckley — when he was president of Bell Labs, that was later on — called me up to his office and I was shaken as to what it was all about. When I arrived he asked me to sit down and then he started out by saying, "Pearson, you're a problem." He had actually asked me up to congratulate me. He then said, "You have the highest salary in Bell Labs for anyone in your age group." Then he announced my new raise.
Did Johnson and Buckley have a close relationship with each other as far as you know?
Yes. However, when Kelly came along, Johnson didn't have as good a relationship with him.
I'd like to talk about that with you later on. What about Jewett, was he in the picture at all?
Well, he was never at West Street. He was down at AT&T Headquarters. He would come around once a year to visit and they would pick certain laboratories for him to visit. And then we would give him a little speech on our work and a demonstration.
What was your impression of Jewett?
He was a very nice man too; a very knowledgeable man. I remember one year he came and I gave my little speech, and at the end, he said he was very interested: "I wish I could work in your laboratory rather than in my office down at AT&T." So, that made me feel good.
He was one of the first research oriented people in the Bell System. Did you know Darrow at Bell Labs?
What was the nature of your interaction with Darrow?
He and Davisson had an office together.
I didn't know that.
He was on the floor below me, maybe two floors down. Darrow didn't have too much interaction with people. He was interested in the printed page. However, we all followed his writings. I often wondered just how applicable it was to some of our work. You see, it was more on so called modern physics.
Did you ever lunch with him, or was he somewhat aloof?
He was a little aloof, but I ate lunch with him, yes.
Would he be interested in what you were doing?
If I had lunch with him, I'd usually go along with Johnson; I was the junior member then. I don't remember that I ever had lunch with Darrow alone.
The statement was that it takes a good experimenter to keep a theoreticians nose pointed in the right direction. Not a very formidable Japanese statement, but then... And then I went on to say that certainly research in Bell Labs someone kept the contributed their part in the success of the organization. You see there was this professor in Japan that was at some research laboratories a few times.
Were you interacting already in the early 30's with Becker and his group, with Brattain and Sears?
Becker at first reported to Davisson. And then he was made a supervisor parallel with Davisson.
Were you aware of what he was doing?
Sure. I was a good friend of Brattain all the time and he worked with Becker — and also of Ray Sears.
When did that friendship begin?
With Brattain? Well, we used to play bridge. Not too long after we went back there. I can't remember. I've always known.
He also came to Bell in '29. So you were contemporary with him and of Sears also. We were talking about Brattain and Becker and Sears, and I was wondering whether you were in touch with their work on copper oxide in that period, and what you thought of it.
Oh, yes. It was interesting but I wasn't too excited about it. But there again, we knew each other and were in adjoining rooms and talked about our problems.
Did either Sears or Brattain ever help you with something that you were working on?
Sure, yes. We were all interested in each other's work. It was a small group then. What was it? There were probably not more than 3,000 people at Bell Labs in those days, were there? Or were there that many?
I don't know that number offhand.
And they didn't have all of the various laboratory locations then.
Were you aware of any changes in the research that you were doing when Fletcher replaced Buckley around '33 or '34 as Physical Research Director? Or was that just an organizational thing that happened above?
That was an organizational thing that happened above. Of course, Fletcher was interested in his acoustics work and there for a while he didn't pay much attention to us. But later on, he became better acquainted with our work.
I'm interested in something that Brattain mentioned in an interview conducted by Charles Weiner. He mentioned going to the Michigan Summer Symposium in 1931 and attending Sommerfield’s lectures on electron theory. When he came back to the Labs, he gave a series of lectures at the Laboratories to inform some of the researchers there of what he had learned. Do you have any recollection of that?
No. Then you probably didn't attend them.
I remember symposiums later, after Shockley organized them. I don't remember this one.
This was apparently a series of about twenty informal lectures he gave. Eventually, I think we'll be able to see all that in Brattain’s papers. We haven't talked about Wente at all. Did you interact at all with Wente?
I knew him and I went to lunch with him more than I did with Darrow. He was the one, of course, who developed the condenser microphone. He had a farm upstate, not far upstate but in the Catskills, that we used to talk about because I had a farming background.
I see. But you were much closer to Goucher and Brattain.
Yes, Goucher, Becker, Bozarth and Johnson.
And Ford, who is he? G. T. Ford.
Gaylon Ford worked with Johnson. When Kelly was head of the tube department, he worked in that area. And then they had a big shakeup after which the job was no longer available. Much against his desires, he came over to work with us.
I'd like to ask you a question about you’re going to Columbia University at this time. How did you coordinate going to Columbia with research at Bell Laboratories in this period.
This was during the Depression. First, we were working five and a half days per week. Then it went down to five days and then it went down to four days and then it went down to three and a half days and finally, I don't know, even lower than that. So we weren't busy all the time at Bell Labs and I was interested in this. Of course Professor Bergen Davis at Columbia was a famous X-ray man and so I went up there and continued some experiments related to the work of my thesis here at Stanford. At Stanford, I'd used photographic methods — at Columbia I could use ionization chamber methods.
So your work at Columbia tended to be experimental. Did you take courses? Who did you study with?
I'm having a hard time bringing back these names.
Did you take Rabi's course?
What was that on — Atomic Physics?
It was on Statistical Mechanics. And who was chairman of the department? I'm going to have a hard time recalling these names.
Rabi was not chairman of the department at that time. It was George Pegram.
Were you working towards a degree at Columbia?
Yes, I'd passed the Ph.D. qualifying exam; I took all the courses, did my thesis, which was accepted, and then had to take the final exam. I never took it because it was a two day written or oral or something like that, a big deal, and I was in charge of — well, this is my excuse now. I was in charge of a group in Bell Labs and we were going great guns and I saw other people who spent too much time getting their degree and didn't make out at Bell Labs so I wasn't going to do that. And my boss, and Fletcher, and everybody else said that they considered me as a Ph.D. even though I didn't take out all that time to study for the final. Later my alma mater gave me an honorary degree, so I have a Sc.D. rather than an earned Ph.D. Since coming from Stanford, I've put out thirty Ph.D.'s.
Did you pay for your tuition at Columbia
Bell Labs paid that. That was part of the educational program. No, I never paid anything. I was living up in the Bronx those first few years and it wasn't far. I would just take a different elevated subway train.
Who was your thesis advisor at Columbia?
Well, he wasn't really a thesis advisor, he was just a name. I can't remember him. Bergen Davis, of course, is the one I worked with. But he retired.
Now the noise paper that you worked on…
Where is that list? I can show you the one that was accepted for my thesis at Columbia.
Your thesis was, "Shot Effect and Thermal Agitation in an Electron Current Limiter by Space Charge."
I didn't have to write a special thesis, this is a published paper on work which I did at B.TW and they accepted the published paper as the thesis. I remember I gave a seminar on it at Columbia.
Well, now the fluctuation noise paper goes further than the work of Johnson and Nyquist and it also extends Schottky's treatment. And you did this not only in one paper, but you have a whole series of papers and memoranda, and even a Bell Labs Record article on this. I notice that not everything you wrote was published; a lot of technical memoranda never were published. I was wondering whether there was any stopping of any publications like these at Bell Laboratories. Have you ever run into that?
No. Of course, you didn't publish as many papers in those days as you do now. In those days, I remember when I went to BTL my goal was to have one published paper and one patent per year. In fact, Buckley said that was the goal of the research department for each technical staff member to produce a patent a year. And he didn't say so, but my own goal was to also produce one paper a year. But these days, in order to rate, you have to publish a half a dozen of them.
So they were urging you to get patents — Understandably.
And by the way, I did average a patent a year, all the time I was at Bell Labs. Likewise, when I came to Stanford, the provost suggested a goal of one Ph.D. per year. I have averaged two a year.
This paper for the Bell Labs Record, was that requested? Was it written by you, or through an interview? I'm trying to learn how these technical departments...
I wrote it, but it was requested and then the editor rewrote it according to the approved style.
What caused you to move over into carbon microphones from vacuum tube noise? That happened in about '36.
I think it was just a natural way to do things. Christensen was a good friend of mine and he had a problem there and I just cooperated with him and did it.
This work on metallic bridges between separated contacts looks, from reading it, as though it goes along a new direction from the earlier work.
Well, you see we were working on contacts. We had developed this instrument so that we could move things very precisely.
This is figure 1 on page 471 of the Bridges article.
It's a cantilever bar apparatus for moving distances of micrometers. We were using this in the noise studies and I think this is something I just noticed, that current flowed just before contact. It was an interesting phenomenon, so we pursued it. I don't remember anybody ever urging me to do it. Or ever, urging me not to do it.
And then you never went back to that.
In 1938 you were moved over from Johnson's group into Becker's. In fact, you and Sears seem to have changed places.
Before that took place, I remember Johnson called me into his office one day and he wanted to know if I would like to work on... well, Buckley had sent a memorandum asking for temperature regulators for buried cable. Johnson wanted to know if I would like to work in this area. Of course, no one likes to change their jobs but I said, “Fine” and we agreed that I would spend a portion of my time on this problem and that's where thermistors came from. This continued on and it was very successful. Then it was decided that the work fit in better with Becker's area than it did with Johnson's. And, well you asked me about Ford. He was the one who was brought from the tube shop to work on this. And then he later went to work on something else.
Let's see if we can date that time. Ford wasn't working with you yet. Ford is here with you in 1934. But this move didn't take place until '38.
Yes, that's what I was saying. He first came over to work on change of resistance with temperature. And he was working with a sulfide compound. And then, let's see, what happened to him. He went someplace else and Johnson called me into his office and asked me if I would like to carry on Ford's work and we agreed that I should do it part time and still work on noise. But I said I didn't want to work with sulphur, it smelled too bad. I said if I work in that area, I'm going to use some other materials. So I made a study of that. First I worked on boron and then on a combination of oxides. A lot of my patents are on such materials and devices. These devices are still used today in the buried cable system as volume regulators.
I see, so that's how your thermistor work began. We are now in 1938 and Shockley has been here for a couple of years. I was wondering if you interacted at all with Shockley in this period.
There were three of those fellows — Shockley, Nix and Wooldridge. Is that later?
That's in the very next chart, '38. They were put under Fletcher, in a special group.
They shared a single office and were sort of the brain trust.
That's the way you thought of it. Did they know why they were put together, in the same room? Whose idea was it, to separate them out and put them together?
I think they were very smart people and management was trying to have them interact with each other. They were not doing laboratory research work. They had no one reporting to them. Mainly in those days, it was paper studies. By the way, I have to tell you a story. The second summer I was at Stanford my professor came to me 0ne day with a young fellow. He said that this man had just graduated from secondary school. He was going to Cal Tech as a freshman the next year and he asked if he could work with me during that summer to get his start in science. That was Bill Shockley. So I've known Bill Shockley ever since 1928.
I certainly didn't know that. So then when he came to the Laboratories you must have picked up immediately on earlier conversations. Do you remember when this group Nix-Shockley-Wooldridge was formed what people were saying about it?
Well, we sort of wondered what it was all about, but at least I thought that these were very promising young fellows. And they had bright futures at Bell Labs and they were putting them together as a sort of management training sort of thing and in addition to react scientifically. That was my own personal opinion; it may have been something different.
Yes, I've heard something a little bit different from each person. I'm particularly interested in this group because it seems to me to represent the beginning of a more fundamental orientation at the Labs towards basic solid state physics. It seems to me they were not interacting with others very much.
Yes, that is right.
And that Fletcher didn't have terribly much to do with what they were doing.
That's right, they were on their own.
I was curious as to who set up the group in the first place. I was wondering if Kelly had anything to do with it.
I suspect Kelly had a great deal to do with it. I might say that Nix was kind of a maverick. He was very difficult to get along with. He could get along with his peers, but I don't know of any boss that he ever had that within six months wasn't considered an SOB by him.
Did you and Nix interact scientifically?
Not too much.
What about Wooldridge?
I didn't interact with those fellows. Not very many people did. Of course, when the war came along and we were working on entirely different things and Wooldridge was my boss.
Well, we'll get to that very soon; we're in '38 already and almost up to the war. I want to ask you a question about a study group that began in this period that I believe Shockley organized. Wooldridge was in it, and Nix was in it and Brattain was in it, as well as Alan Holden and Howell Williams... I was wondering if...
I can show you the text we used.
Oh, Mott and Gurney. I gather then that you attended the seminar also.
Yes I did. I remember we took turns giving the lecture and if you'll look in the part of this book which has a lot of pencil marks in it, you'll find that was the part on which I gave a lecture.
You must have talked about the perfect ionic lattice because that chapter is all marked up.
It looks like it.
Could you tell me a little bit more about that study group? For example, how were the members invited into it? I have no documentation for facts such as these.
You had to be invited into it. It wasn't an open thing.
Who invited you, do you remember?
No, I do not remember.
Did you have trouble with the material?
Yes, but it was very worthwhile for me. I was not as well prepared for it as these other guys —
— who had had more quantum mechanics in graduate school. Oh, I see you gave a lecture on electors in polar crystals also. What about Holden? Did he have trouble in the study group? He also came to Bell Laboratories in '29, so he couldn't have studied quantum mechanics.
I don't remember about Holden.
Who would you remember? Do you remember Howell Williams?
I remember Howell Williams.
He was there; he was working on magnetism at that time.
Yes, he was working with Elmen I think.
I gather that this group met once a week.
I don't remember how often.
And it was informal.
I don't remember whether it was in hours, or out of hours, although I think we met during working hours. I couldn't be certain.
Someone told me it began at 4:30, which was before the working day ended and that then it went on after hours, also that it met once a week for a number of years. Do you remember some of the other texts? Was this the principal one, Mott and Gurney?
This is the principal one I remember.
Do you remember if Bozorth came?
I don't think so.
Yes, I don't remember specifically, but I imagine he did. I don't exactly know when Fisk came to the Labs.
He came in '39.
I'm pretty sure he joined the group after he did come.
What about Charles Townes or Joe Burton? I'm mentioning names of people who might have been there and would just like you to tell me whether or not you remember them in the group. I have really no other good way to get at this information than by trying to pick your memory and those of others who were in the group too.
I'm hazy. You should ask Charley Townes over at Berkeley and Joe Burton who is at the American Institute of Physics in New York.
Townes is in France just now. I hope to ask him when he comes back. Do you know if Kelly had anything to do with this group?
He never attended.
Do you think he might have suggested that the group be set up?
I imagine these guys — Shockley, Nix and Wooldridge on chart)… this is one of their ideas and I’m sure that Kelly encouraged it.
You see, there's a story repeated in some informal Bell Labs publications that I'm trying to check, that in the mid '30s, or certainly after 1936, after Shockley had been hired, Kelly was already talking about setting up a basic solid state physics research group.
When did Kelly become Director of Research?
Yes, I think people in general, attribute this solid state push at Bell Labs to Kelly. That is, it was a management push.
I have so far found no documentation, no memos. Nothing I've seen conflicts with it. Let's see, you gave a talk on thermistors to the colloquium in May, 1940. And Shockley wrote a nice little summary of your presentation. Was the colloquium another important way of learning about the new physics? The study group was one.
Yes, that was just a small group. The colloquium was open to all members of the technical staff and it met every two weeks or something like that. And we had inside and outside speakers.
I have here a list of many of the talks and speakers and I marked some of the talks that might have interested you in particular. I wonder if you could glance at this and share some of your recollections of the colloquium with me? What I am trying to figure out is just how important it was in the research organization.
It was a broadening influence. And I always attended them, or whenever I could. I remember that if you were the host for the outside speaker, you always went out to dinner at Charles in Greenwich Village. And the company paid for it and you took the speaker out. I was chosen to do this two or three times. One particularly, was Bill Hansen who was a classmate of mine at Stanford. I asked him to come and I was the host. This must have been in the early forties.
I stop somewhere in '42. Here's Hansen, 1941. (off the tape — interchange about number of persons who attended the Colloquium)
I was going to say that most of them were in the 50's, 60's and 70's attendees, that's a hundred. And then I look back over here at the one I gave which had 130 attendees.
Did you attend Sommerfeld's lecture when he came in 1929? Do you remember him?
I don't remember. There were only 44 people there.
Did the talks stimulate discussions?
Oh yes, Frederick got 231 people. He probably gave a demonstration on three dimension sound.
Here I see a joint colloquium with Brattain and Becker in '32. Not many people.
I remember this one. He's quite a character, Henry Eyring. He's dean at the University of Utah.
What caused you to remember that one in particular?
Well, his stage presentation.
What did he do?
He talks very fast and very fluently. He has a way of his own, very informal.
Now this is a symposium that you took part in in 1933, on thin metallic films.
I remember I wrote a memorandum on that, too. Thin metallic films have a high negative temperature coefficient of resistance.
Do you remember whether symposia were a regular feature of this colloquium? I noticed one other symposium on the positive electron. Rabi was there and Darrow and Breit. This one in '33 is all Bell Laboratories people.
Well, I think it was just to bring the people up to date on interesting current subjects. Weinhart was the glass blower and technician and Johnson was the boss and Christensen and I were working on this subject.
Now, before we talk more about thermistors, I would like to ask you one question about Ohl’s work on silicon in the late '30s. Brattain recalls being called into Kelly's office early in 1940 to witness a tremendous photo emf produced by Ohl's silicon when light from a flash-light shone on the pn junctions. The photo emf was so large it surprised Brattain.
By the way, when you read these things, if you're interested in this topic, you'd better read this article: "Sub-histories of the Light Emitting Diode." I don't know whether to believe all that he puts in here or not. He claims that it was all done in Russia many years before it was done here.
That would be very interesting to trace. One can check that in publications.
Loebner gives references, publications and so forth. In those days we didn't keep up with the Russian literature very much. But he says that pn junctions and the photo effect and so forth were prior art in Russia.
I'll have to look at that. Were you aware of Ohl's silicon pn junction work? Was that something people were talking about at the time it was done?
Well, let's see. Ohl was not at West Street. He was at Holmdel. We didn't see much of their work. But we heard about it.
Was it considered very important?
Not until the war came along. Then it was very important for high frequency detection, radar usage.
Did you know Wooldridge before 1943, when you were moved into his radar section?
I knew him the same as I knew Nix and Shockley, although I knew Shockley from before.
You knew Shockley better. And Nix you didn't talk about too much with him, the details.
Oh we talked a lot.
Wooldridge was working on secondary emission, magnetic sound recording, and television.
I do not remember that Wooldridge worked on television.
Well, it was only for a short period. He wrote a memo on projection television-something that Kelly was interested in. But then the Bell System decided not to go on with the television research. They kept changing their minds and going back and forth about that.
I remember one colloquium on the top floor, the twelfth floor, of the West Street building — I don't know whether it's in your list or not — where Ives gave the first color television demonstration. It was a great big wheel with a lot of prisms that rotated. It wasn't electronic, it was optical.
Must have been very impressive. I don't know when color television first began to be demonstrated.
Well, that was before they had black and white commercial television.
So, it must have been in the early '30s.
Yes, to the best of my memory. Let's see, have you had any interviews about Ives.
I don't know too much about Ives. I gather that he was an extremely fine researcher.
This may not have been a colloquium. This was a demonstration up in the auditorium and we were invited to attend a few at a time. So I guess it wouldn't have been a colloquium.
He gave several colloquia. Was he a big influence in the Laboratories at the time? Did he influence you much?
He didn't influence me, but he influenced people in other departments.
I see later Ives talked about special relativity. He seems to have done a lot of things.
He was quite a guy. He was a fine painter also.
Let’s talk about thermistors. Now you told me how you got started on that work. You carried out that work in collaboration with Becker.
Well, I started it with Johnson. It had been going on for a year or two before Sears and I traded jobs.
And then took over and Johnson stopped working on it, or how did that happen?
Well, I was the only technical staff member who was working on it. And when I transferred, the job went with it. Sears was probably working on thermionic emission. And that came to Johnson. Then getting back again, when Kelly took over — as I said they were never very friendly — then Johnson was demoted and moved down. If you will look at the chart just before he left, you will see that he was no longer a department head.
I do remember at some point wondering why that happened. You're implying it had to do with some sort of a run in with Kelly.
There was a clash of personalities.
I wanted to ask you some questions about thermistors. You said in one of these articles, 1946, they're about fifteen years old. So that dates the earliest about '31 or something like that. In a '32 paper you referred to a Russian paper. Do you remember who invented them?
This is just a phenomenon of the change of resistance with temperature. Joffe over in Russia worked on these sorts of things and he also worked on them in Germany. We coined the term thermistor.
I think it was Davisson that suggested it. What it is is a thermal resistor. No, we didn't originate it: We just put it to practical use. I have a dozen patents on such devices. I think probably I was the guiding light at Bell Laboratories on the development of thermistors.
I was wondering who at Bell Laboratories first noticed that this phenomenon was one that deserved detailed research.
It was Buckley who sent a memorandum to Johnson saying that he would like to have something to regulate the repeaters on transcontinental cables. He didn't say what the phenomenon should be or anything. And so Johnson and I studied this thing for several months and decided that this phenomenon of semiconductor resistance versus temperature seemed to be a promising thing. And we took off.
And then there are quite a number of technical memorandums on this, but no comprehensive publication until this 1946 one.
Publication was prohibited during the war. You see, we were working on infrared bombsights using thermistors for detectors and that was hush hush.
Did you develop the thermistors further during the war in connection with the infrared bombsight work and then simply could not publish for reasons of time and secrecy?
Secrecy was the main thing. The government wouldn't permit it.
But did the work go on?
Yes, but it was directed toward the war effort. We still worked on thermally sensitive devices, but they were in the form of thin films now, so as to have a short time constant. Because, you see, we wanted to scan an area which we could use in a telescope at night and detect a man a quarter of a mile or so away.
Sometimes you hear people tell how "all research stopped during the war."
No, its direction was just changed.
I keep on getting more and more examples that are beginning to convince me that on the whole the war aided a lot of the research that went on rather than stopped it, in part because of the large amount of money that was put in and because of the accelerated effort. I wonder how you feel about this.
In my particular case, they were very anxious to get this thing going. I wasn't a department head; I was a supervisor and had a large group working with me. They brought people in from the telephone companies and I had several: one from the Pacific Telephone Company, another
These people here?
Kenneth Haber was loaned from Pacific Telephone and Telegraph. Lowden was loaned from Illinois Bell.
What specifically were they brought in to do?
To help on this bombsight effort.
So the major difference was that the work was refocused: You got a lot more help and money.
So, I gather things came out that might not have otherwise. Can you think of examples of developments that came out as a result of the war that probably wouldn't have had the war not intervened?
That was used for civilian purposes afterwards?
Or just in research.
Well, in my own area, the snooper scope. Are you familiar with the snooper scope? That's a device for seeing in the dark. It's used in research.
What was the nature of your collaboration with Green and Becker on the thermistor paper after the war? Who wrote the paper?
We each wrote different sections. By the way, we got the IEEE prize — then it was called the IRE or IEE or something for the best paper of the year for that.
It is a very nicely written paper.
We also received $100. I owned a farm, forty-six acres, and rather than spend that money in any other way, we invited all the people who had worked with us and their families out, and we had a big picnic and blew the $100.
The paper includes some history and the theory is well done. And it includes a very impressive list of references. Looking at this list of references suggested to me that you probably were attending that study seminar, because the books noted in the references were being discussed there.
Do you get hungry?
I do get hungry, are you hungry? (Pause for lunch)
We are resuming after a short break for lunch. During lunch, you told me how you moved into the role of a research director. I wonder if you could repeat part of the story on tape.
I had been asked several times during the 1950's to become a department head at Bell Labs and I always told the management that my interests were in being a contributing scientist rather than in directing other people. And so each time it would die down and then come back again. Finally, in about 1957, I think it was Hendrick Bode, who was Director of the Physical Research Department, called me in his office one day and said "Pearson you owe it to the world to become a department head.” He said "you are productive as a contributing scientist and you should train young Ph.D.'s to also become productive." Well, I told him I'd think about it. So I talked with various of the other department heads and finally agreed to take the job. Bode said that I could spend fifty percent of the time on my own as a research scientist and the other fifty percent of it as a manager. Well this worked alright for a while, but as time went by, it took more and more time, the personnel problems and salary problems and this and that. So, when Stanford asked me to come, that was one of the contributing things that made me decide to become a professor. Here I am training young people but I can also do research on my own also.
So your research really began to get pushed out at Bell at that time. I would like to go back to the article that you were awarded the prize for, the '46 paper. In a footnote here, referring to thermistor work, you thank Jack Scaff, Henry Theurer and also Gordon Teal. That indicated to me that already before the war — this was published after the war but it was done before the war — you were working closely with materials researchers.
That was the silicon conductivity versus temperature curves. Of course, Theurer and Scaff were the people who produced the silicon. Silicon is not used in thermistors. It gives the background of the temperature curve characteristics.
What I'm trying to get at is the nature of the interaction between the metallurgists and the physical chemists and the physicists and others.
It's the combination that makes things go, that makes things hum. Metallurgists always thought that the physicists were hogging the glory. We tried to be fair, but one can't get along without the other. It's a team combination.
This joint effort seems to be one of the great strengths of an institution such as the Bell Laboratories. It doesn't seem to be equally true at universities, where departments tend to be much more separated from one another.
I don't know whether this is in your notes or not, but when we were still at West Street working on thermistors, the management on purpose established a large laboratory room and put Dick Grisdale and his people together with me and my people in that room, so that we would be right side by side. And that's one of the things that contributed to the success of the thermistor.
Was this in the '30s?
Yes, late '30s and early 40's.
Now, you moved out to Murray Hill after the war.
No, we moved out before the war, or at the beginning of the war. I think we moved out there about '42 or '43. It's in the records. We were working at Murray Hill during the war.
So this had to have happened in the '30s.
Yes. That arrangement was not continued after we moved to Murray Hill. I moved to Murray Hill and Grisdale stayed in New York. After we moved to Murray Hill, Walter Brattain and I shared a common laboratory.
I'm going to ask you detailed questions about that in a moment. I just want to ask you a few general questions about research during the war at Bell, about the general atmosphere. Now you mentioned that some people were added from various other places.
Oh yes, some people were brought in from the operating companies; "loaned” to Bell Labs for the duration.
There also seems to have been an increased number of consultants during the war. Do you have any recollections of Slater and Seitz coming down?
The one I mainly remember is Peter Debye.
Did you interact with him?
Yes, maybe this was a little later, after the solid state group was set up. He came down once a month from Cornell for a couple of days after Shockley had organized this group from which the transistor came. We had a two day conference with him every month or so.
He's the one I reacted with the most. I do know that Seitz came, but I didn't react with him much. He, by the way, is a Stanford man. He got his bachelor's degree at Stanford.
What about interactions during the war with other laboratories, both industrial and university institutions? Were they intensified, or about the same?
Unfortunately, they were decreased, because everything was secret. A good way to retard progress is to make the project secret.
I was under the impression that MIT worked closely with Bell Labs.
That’s right. Not MIT itself, but the Radiation Laboratory at MIT.
I thought there were some connections with Purdue and Columbia, but I'm not at all clear about them.
Yes, there were connections, but given people from Bell Labs were transferred to these laboratories, to Columbia at least. That was not Columbia University, but a special defense laboratory like the Rad Lab. (Big gap on tape due to an inadvertent erasure. The following was supplied during editing.)
What were interactions like during the war with other laboratories whose work was not closely coordinated with the Bell research? Perhaps you could answer in terms of some examples.
A number of defense laboratories were organized at various universities. These included MIT, Columbia, Johns Hopkins, Purdue, Michigan, etc. My only contacts were with MIT and Michigan.
During the war, a number of consultants were added to Bell's staff. Do you recall any of these? How did you interact with them?
I had little contact with these.
You were, during the war, a civilian with the OSRD and the Navy. Is that correct? Who directed your work? Where did you carry out the work? Was it supported by the NDRC, Navy, or Army?
In the early part of the war I was connected with a group at MIT under NDRC. The committee chairman was Professor George Harrison, who I had known at Stanford, and the secretary of the group was Julius Molnar who came to Bell Laboratories after the war and eventually became an Executive Vice President. J. A. Becker and I made many trips to Boston to attend committee meetings.
What were the principal projects you worked on during the war? Who suggested your studies of infrared devices and why?
As the war progressed I was asked to join the Naval Research Laboratory in Washington to work on the proximity fuse. I was pleased when it was decided that I should remain at Murray Hill and join Walter McNair and Dean Wooldridge who were developing bombing through overcast systems using radar techniques. This was a very large effort with support from the Air Force. During the latter part of the war I returned to infrared problems under Navy sponsorship. In addition to device and system development the work included many hours of bombsight testing in the air.
Do you feel that your work during World War II influenced your later work on semiconductors?
No. The work during the war was a diversion from my earlier interest in fundamental semiconductor research.
I'm particularly interested in hearing about how you came to be added to the new solid-state group of Morgan and Shockley. Who invited you to join? What were the choices you faced?
Walter McNair asked me to remain with his military research group but I told him that I preferred to join the new solid state physics group of Morgan and Shockley. The transfer was then made in accordance with my wishes.
Who did you work with most closely in the solid state group? What was the nature of the day-to-day interactions?
A common laboratory was set up to house Walter Brattain and me, together with our technical assistants. (The following resumes the original interview.) At that time, also, Shockley had returned and was beginning to set up his solid state group. And I told the management that I would prefer to go with Shockley rather than into military research. So I was terminated in military research at that time to join Shockley's group.
I see. Shockley was in Washington. But then he came back. And so in '45 here you are about to be moved from McNair to Shockley and then later on in ‘46 you are in the famous Morgan-Shockley group. Did Shockley speak with you and invite you in, personally. You say you had a choice. How did you know what the choice was?
I don't know that we had any specific conversations. But I'm sure he and Morgan must have. Otherwise I wouldn't have been there.
Do you know who set-up these three groups? I mean who were the people who were having discussions about the reorganization of the entire Physical Research Department?
Well, I'm sure the instrumental people were Fisk and Fletcher and Kelly, together with the Department Heads.
Wooldridge says he had nothing to do with the discussions. He said one day everybody was invited into a big room and told where to go.
I expect Kelly had more to do with it than anyone else.
According to Wooldridge, Kelly just wrote the new organization out on the board; from then on different people were going to be going to different places. Maybe Fletcher could give me some information.
Fletcher was not a strong minded person, but Kelly was.
Do you think Fisk might have had more to do with it?
He might very well have.
How was the new group explained to you? Do you remember? Were you aware that there were three brand new groups: the Wooldridge, the Fisk and the Morgan-Shockley groups? According to the documents, they were all set up at the same time; they all have case authorizations starting at the same time. They are all typed up in the same way. But, actually, the Wooldridge group wasn’t really new; it had existed before in a different part of the organization.
There are a couple or three things here you might notice. These folks, Bozorth, Goucher, and Mason lost their department head standings.
Were there hard feelings about this?
I'm sure they felt badly.
Their names aren't in big letters anymore on the chart. Does that mean that their salary went down, too?
No, just their status.
Were you aware of any difference in the orientation, broader orientation perhaps, in the new group than in the earlier group that you had worked in?
For the last five years we had been working on secret projects. We felt free as the wind now.
But compared to the period before the war, '39, '38.
Well, it was back to the status of the earlier days, only this was much more sophisticated work than it was before. You were asking about the cooperation between chemists and physicists. Morgan is a chemist and Shockley is a physicist. So this is one way they were trying to bring different people from different disciplines together.
I thought there was some tension between Shockley and Morgan.
I didn't know about that. There were tensions, but not that I know of between those two.
Now what about the subdivisions of the solid state group? There was the magnetic subdivision under Bozarth; the Shockley group was focusing on semiconductors; and Morgan's group was in dielectrics. What was Mason's group doing?
Propagation of sound in solids.
Did the whole group work in unison? Or did the subgroups act like different departments?
I don't remember any friction. But undoubtedly these people who had been department heads and were not anymore, they continued along the same sort of lines.
You see, it's always very difficult to know whether a striking organizational change that is well documented on the organizational charts really means anything in terms of what the day-to-day researchers were doing. I tend to think that most often it didn't.
As far as I was concerned, I was so happy to get back on fundamental science, away from the war effort, that I was pleased.
Did you interact with people in the other groups more than before?
I would say the same. There was a mixture of chemists and physicists here. Gibney, who was in our group, was a chemist.
I notice you worked on superconductivity for a while with Gibney.
I really didn't work on that too much. There was an announcement by Professor Ogg, at Stanford, that he had obtained superconductivity at liquid nitrogen temperatures. Of course, the Bell System was very interested in this and since I came from Stanford, they appointed me to go out and look the situation over. And so I spent several days out there with Ogg. Of course, we were all skeptical and even more skeptical after I had been out here. I went back and talked with, I forget who it was... some of the magnetics people. We concluded that the way to definitely determine whether it was superconductivity, or whether it was metallic filaments that were being produced, would be to measure the susceptibility, which Gibney and I did. We proved that it was not superconductivity and published this little note. One thing that pleased me about a year later, I saw a Russian article where they had done the same thing and they said they had corroborated our results.
Then, you never did any more with that?
No, that was just a little side effect.
Then you began doing lots of work with silicon and germanium. And silicon and germanium was all done in this group under Shockley and with various collaborators.
No, the silicon and germanium materials work was carried on in the metallurgy department.
More than once you collaborated with Struthers and Henry Theuerer.
Theuerer's a metallurgist.
Yes, he's a metallurgist, but you at that time were working in this Shockley group in collaboration with...
Struthers was a radioactive man. He had charge of the radioactive supplies. And Theuerer had charge of materials.
And with Bardeen you studied electrical properties of silicon, and silicon alloys. Now, Brattain talks a lot about this group under Shockley, about how close the working relationship was, how you and he were the two experimentalists who had been working with semiconductors.
Bardeen was the theoretician and a darn good one too. And Brattain and I were experimentalists. Foy was my technician and Gibney was a chemist. Griffith was Brattain's technician I believe, and Bert Moore was a circuit man who was very essential to the group. He put together circuits for testing and so forth. Not just simple ones; complicated ones.
Was he sort of a technician?
No, that was why I said a very sophisticated one. He was a member of the technical staff. He also had been at Whippany, I believe, before he came here, in the military area.
Who actually suggested focusing on silicon and germanium? I know that at a certain point the group began to focus on that.
Germanium was highly successful during the war for high frequency detectors. And so it was a natural follow over for us to consider it because we worked on this during the war. Silicon was farther behind. It has a larger band gap so it works differently than germanium. Once they got started on germanium, it was hard to get them off onto silicon. But a few of us, realized that silicon was the thing of the future.
Because of its characteristics, it's larger band gap. We were plugging silicon for a while as a losing cause, but then people saw the light and then we were off on silicon. Germanium is used very little now, as you know.
How important do you think Ohl's exploration of silicon in '38 was to the semiconductor developments that followed at Bell Labs? Having discovered that silicon works very well in high frequency microwave detection, he got the metallurgists working on making pure silicon and that's how the pn junction was discovered.
Well, I think this was very important in leading the way. I never felt he followed up on this too much. You see, he was off down there in Holmdel away from the main group. He was unable to follow through on this after he had found the effect. Maybe that's a biased opinion. Other people might not agree.
In one of his transistor articles Shockley wrote "We assigned highest priority to the primarily scientific aspects, but in our selection of emphasis, we did choose those scientific aspects that were related to the problems that blocked our approach to the long range practical goal, the creation of a semiconductor amplifier later to be called the transistor.” He implies that that the transistor was something that they were looking for right from the start.
I think that he had thought along these lines prior to the war.
And you feel this is an accurate description of the group's aim?
From hindsight, you can say that. When we were actually in it, we were groping in the dark to a certain extent.
But were you consciously looking for something like a transistor? Or did you consider your main job to achieve a better understanding of the semiconductors you were exploring?
In my personal case, I was more interested in the scientific aspects of the material itself. I wasn’t working with transistor-like structures, as evidenced by that paper by Bardeen and me.
There is actually — there are a lot of papers; this one.
Yes, that probably.
I would say this was the most important paper that I was ever associated with. Certainly it was the most popular. We ordered a thousand reprints and they were all gone, and then ordered another thousand and they were all gone, I don't have any of them left. It's been referred to by people as a classic paper in the field.
And this was done just at the time as the transistor work was being done, is that right?
Yes, Brattain and his group were working on surfaces and I was working on the body properties. That's what this is.
Now this paper is both a theoretical and an experimental paper.
Yes, Bardeen was the theoretician —
— and you were the experimentalist? Was it divided up cleanly in that way?
No, we cooperated.
You each did a little theory and a little experimentation?
No, I'm not capable of doing very much theory.
I'm trying to get at the nature of the collaboration between you and Bardeen on this research and in writing the paper.
Well, a theoretician can’t write a paper without experimental data, and an experimentalist can't write a paper without some theoretical analysis. And this was a cooperative effort.
That answers it. There is a question I forgot to ask you before. Teal claims in his article in the recent IEEE issue that he introduced the first germanium research at Bell Laboratories. Do you agree with that?
I wouldn't know. That would be between him and Scaff, I think.
In this paper I noticed that you got your silicon from DuPont.
Yes, the raw material. But then it was processed by Scaff and Theuerer. Isn't that what it says? This was just the purchase of the raw material from DuPont.
Earlier the silicon had come from Germany, hadn't it?
Before the war, yes. But, of course, during the war that supply was cut off.
Now, simultaneously with this work on silicon, you worked with Shockley on the modulation of conductance of thin films of semiconductors by surface charges.
Yes, that paper came out in the same issue of the Physical Review as the transistor announcement.
Were you actually working on them simultaneously or did the papers just come out simultaneously?
No, we were working on them simultaneously.
And what was the nature of the collaboration with Shockley?
Oh, he was the idea man and I was the hands, I guess.
Did he do any experiments?
Very few, if ever.
People sometime say he was both an experimentalist and a theoretician.
He wouldn't be as famous today if his claim had to lie on experimental work. I'm not degrading him. He's a very top flight theoretician.
I didn't hear it that way. We were talking earlier at lunch about some of the various different stories about how the transistor came about. The two that have been published most widely, or circulated most widely are, I believe, the accounts of Brattain and Shockley. I was wondering since you were right there, whether you have your own ideas about what the main themes were in that development?
Well, I think I don't know what you mean by the Brattain story and the Shockley story — it seems to me, that Gibney had a great deal to do with this too. They were studying point contacts, all in germanium, and they were putting some of what they called "goo" on the surface. And they were trying to understand the effects that went on.
I understand that you had a great deal to do with it also.
Oh, yes, I was in there pitching, too. However, I was working on the body properties more than the surface properties.
At the twenty-fifth anniversary of the transistor, they wanted me to come to the celebration and I said I was going to be vacationing in Tahiti. They said that they'd fly me to Murray Hill and then back to Tahiti.
Did you go?
No. I thought that was too long a flight though I would have very much liked to have been there. (Referring to model of original transistor.) Here are two points on the hunk of germanium and I guess it's supposed to look like some goo there. The original of this is in the Bell Labs museum. This is just a replica which they passed out to everybody at the party and since I had been invited, they sent one to me.
I would be most interested in hearing in more detail about your role in this whole series of developments.
I said, my role was in the materials of the thing, in the body properties of silicon and germanium. I have several patents on transistors also, of a special kind. But I don't claim any fame in the point contact transistor.
How did your work on the body properties enter into the whole transistor development, which isn't just the point contact transistor?
In order to understand the operation of these things, you have to know the properties of the materials with which you are working. The paper with Bardeen outlines the properties of the material. It puts it on a firm foundation. Then this field effect transistor — that was the first field effect transistor — well, we were trying to understand by putting an electric field at the surface of the semiconductor to get an inversion layer, I don't know whether these terms mean anything to you —
I don't understand them in detail.
How it operates and so forth. It didn't work at all like we thought it ought to. It worked, but a very small fraction of what it ought to. And that was the basis for Bardeen to go on and develop his surface state theory. So there is more to this than just making a device. There is the understanding behind it. And that is what I think my contribution related to.
So for me to really understand in detail your contribution means studying this paper that you wrote with Bardeen in '48?
That's part of the story. There are a lot of papers.
Yes, I have only a few of them here. Electrical properties of crystal grain boundaries in germanium for example, just one after the other, magneto-resistance — but that's later — in germanium.
There's a whole series —
— and those are just published papers. You also have oral Physical Society papers too.
And then patents and technical memorandum that were not published which I ought to go back and study too. Brattain recalls that it was almost a month before Kelly knew what was going on vis-a-vis the transistor in '47. Did you know about it right away?
Yes, because I was in the same laboratory.
You were in the same laboratory as they were.
Well, I signed the...
— you were one of the official observers.
In fact, at the time of this 25th anniversary celebration they put an ad in all the national magazines and the ad was that page of Brattain's notebook with the signatures. I was on a plane flying from Tahiti to Fiji when I picked up a magazine to read and I saw my signature. (Laughter.)
There must have been a tremendous amount of excitement in that laboratory. Do you remember the afternoon when they actually...
What was the feeling, what was the atmosphere? I haven't spoken with anybody yet who was there on that day.
Have you spoken with Brattain?
No, I've only read the transcript of interviews with Brattain by Holden and also by Weiner.
I don't remember anybody jumping for joy but there was great elation. By the way, this man, Bert Moore, also signed it. And he contributed a great deal to the circuiting. He has since died, but he always felt that he didn't quite get his due. So I put in a strong plug for him now.
Is Gibney someone I ought to interview?
You might. Gibney works at Los Alamos. His wife had very bad hay fever in New Jersey and he left Bell Laboratories to go to Los Alamos for her health. I'm sure he wouldn't have left Bell Labs otherwise.
Getting back to that day, it was an afternoon, I guess when it happened?
I'm a little hazy.
Do you remember that special day?
Yes, I remember the speaker and the microphone and the transistor circuit and so forth.
Were words amplified?
Yes, words were amplified. I'm a little hazy; if you really want to know, talk to Brattain.
I'll have to talk to Brattain.
I guess it was the next day that they called the big group in to demonstrate the effect.
Do you remember anything about that occasion?
Well, I just remember the folks trouping through and everybody amazed.
Did everybody realize how important this would be right away.
I don't think so, but it was the goal of our department to do this and here it was. Sometime in this interview I want to say something, but I don't know whether it's time or not. The point contact transistor was the first and it was the thing that led the way and it was of very high importance. Everybody worked on this for a year or two. However, in the meantime along came the pn junction. And then the point contact transistor was dead. It has been of little practical importance since. The pn junction took over for a number of years. But now, the field effect transistor has taken over and there are more field effect transistors presently made than pn junctions. Integrated circuits are the main reason... integrated circuit transistors are mainly field effect.
Has anybody else told you that?
More or less. I'm very glad to have it on an interview transcript so that it's there in the record, and coming from you adds some authority to it. Historians have a tendency to overemphasize the first step in a chain of events.
I'm not trying to degrade the point contact transistor. It pointed the way. But it is of little practical importance now. By the way, I later developed the first useful silicon field effect transistor, and described its operating characteristics at the Physical Society Meeting in Boston in 1953.
How did day-to-day research change after the transistor?
It didn't change appreciably.
Not at all.
This was the first success and we were looking for more success.
How did people at Bell react to the initial policy of keeping it quiet? Was this questioned by anyone? How was it enforced?
We had just come out of the war where we kept everything quiet so this was no problem.
Let's see, then you moved on and explored a variety of germanium properties, Geiger counters and Hall effect, magneto-resistance and there was the hole injection work with Shockley, and Brattain and Sparks. That came a little later didn't it? Or was that simultaneous?
I have notes here on hole injection work. Is that an error?
Let me see the publication. Oh, it is hole injection. You have — This is the long paper of Shockley, Pearson and Haynes. Shockley was the guiding light in the work.
How was all this work coordinated? It seems you were working on several different problems at once. Or would you work on one problem and then another?
No, several things at once. In fact in those days with all these new discoveries coming every day, with a new discovery a day and a new patent every little while, it was quite an exciting time. Everything was new and different then and everything was a contribution. As they used to say at Bell Laboratories, they called me a "cream skimmer.” You know what that means? That I would go along and work on a new phenomenon and publish a note and then stop and go on to another one, which I think is one way to operate.
You certainly worked on a large variety of problems, most of them having to do with silicon and germanium. The magneto-resistance work in the later period was in collaboration with Harry Suhl.
Yes, I might tell you a little bit about that. I had done that work, the experimental part, six months or a year previously. I didn't want to publish it without a theoretical analysis, but I wasn't capable of doing that. I kept waiting for Shockley to do it, but he was so busy that he never got around to it. Finally he suggested I find someone else. So I contacted Harry Suhl and he did the theory on it and we published.
You did some work with Herring, on magneto-resistance. That was much later.
That was the same sort of thing, only on silicon. There's still another one here with Tanenbaum. When Tanenbaum was made Executive Vice President of Bell Laboratories, I wrote him a letter of congratulations. And he wrote back and said he always considered me his Bell Laboratories Professor because the first paper he published after he came to Bell Laboratories was a joint one with me. And this is it.
I was struck by the fact that in almost all these papers you thank a number of people for their help.
These were joint efforts. You didn't do things on your own.
It's true for every one of these papers (indicating small pile of reprints). Let's take the Pearson and Suhl paper. Here we have Conyers Herring, and Bardeen and Shockley and Teal and Foy. This is very typical of the papers that are coming out during this period. Not only are the authors a whole group, such as the group of Goucher, Pearson, Sparks, Teal and Shockley, there is also a group of acknowledgments. In this paper, which has five authors, there are four acknowledgements.
By the way, Walter Bond is here at Stanford now.
And Jack Morton...
These two have both died.
Morton and Moore. Morton didn't die naturally, did he?
No, his body was found in a flaming automobile.
Apparently that is still a big mystery.
Yes, I guess so. I was with him just a couple of weeks before his death. We were at a National Academy of Sciences meeting at Woods Hole, Massachusetts. Well, I think if you want to summarize all this, it's the cooperation of a whole group of experts that makes things go.
In the early fifties you also carried out some alpha particle bombardment experiments. What led to this work and where did it go?
That's the one with Struthers and Theuerer?
Oh, no, that's the one with Brattain. That's the beginning of radiation damage investigations.
I don't think I have it with me.
Well, it would be over there.
I can locate my note on that in a second. You wrote some unpublished technical memoranda on that subject yes and paper number 17. You have at least one published paper on it. I was wondering how that fit in with everything else.
That was during the early beginning of the radiation damage work. In fact, maybe we were a little bit... we didn't treat Purdue quite right on this one. They had been working on radiation damage during the war, and it was secret and they couldn't publish. We had nothing to do with any war effort on this subject although this was after the war, I don't believe that Purdue had been released from their secret code, while we had no strings on us to prevent publication.
Did you continue this kind of work?
I didn't. But other people have and this is one of the important things, for example, in solar cells. The radiation damage that you get from the radiation belts up in the stratosphere deteriorates the cells. Radiation damage is a big field of its own these days.
In the work reported on in paper number 17, "'Conductivity of Germanium Induced by Alpha Particle Bombardment,'' You were bombarding...
...with alpha particles. You see, we didn't have any high energy machines in those days so we were just used natural radioactive alpha particles. They have a certain energy and the particle has a certain mass and it penetrates a certain distance. We bombarded and then profiled, that is we etched off a little, or ground off a little — I've forgotten which we did — and measured the resistivity as a function of depth, and so forth. This is not an application paper, this is an understanding paper. As far as I know, it's one of the earliest ones in this field as I said before, because we had no secrecy strings attached.
Now, the detailed work on silicon, and I guess also on germanium, led into the silicon solar battery.
Well, actually I wasn't working on the solar cell at the time. The goal was not to get a solar cell.
Could you tell me that story or if not, where might I be able to read it?
It appears in that special issue of IEEE. I was editor and I didn't want to write the article, so I asked Friedolf M. Smits to write it. He asked me to send him the background information, which I did.
So that's basically your story then. Well, then we can just refer to that. I have the article here. Are there any things you would like to add to this Smits article?
Well, this paragraph here sort of tells the story.
Yes, the third paragraph.
The second and third. I was trying to make a silicon power rectifier by the way, that and the silicon diode are the most important patents on semiconductors that I have, from sales and so forth. I noticed it was very sensitive to light. Chapin was working on power sources for isolated telephone installations; I brought this to his attention. And together we measured it and, found it to be a very good energy converter.
Were you aware of how important this work would be in terms of applications right at the time that you were doing it?
That was before the day of satellites.
Were people talking in terms of power sources?
Within a year we had a trial as a terrestrial power source to run a telephone system at America vs. Georgia — we put it up on a telephone pole and used it to power a copy carrier system — and it operated for six months without being connected to any power lines. We wrote up a report on it, I didn't write it up, but the engineering people did, saying it was a huge technical success but a financial failure. It costs too much, which is still the case.
The Smits article implies you were not working very closely with Chapin.
I was working with Fuller; I hadn't been working with Chapin. Chapin is an old friend of mine, in fact he went to the same university in Oregon that I did. He was one year behind me.
But you weren't working in the same way with Chapin as earlier you had been working with Bardeen and others.
I had been working with Fuller, because he was developing diffusion techniques, and I was trying to get a silicon power rectifier and needed diffusion techniques to do it. He was in the Chemistry Department and I was in the Physics Department. We collaborated. I was using his techniques.
I see. You collaborated in that sense. You were carrying out the actual work, using their background research.
Yes, I was using Cal Fuller's recipe for diffusion and trying to make a silicon power rectifier. I noticed it was highly sensitive to light. At that time, the most sensitive light converter was the selenium cell which was used in cameras. It had an efficiency of less than one percent. And that cell that Chapin and I tested — that first cell— was four percent. And then within two or three months we had it up to six percent and after another six months it was up to eight percent. This was quite encouraging.
Do you consider this your most important Bell System contribution?
What do you consider your most important contribution?
I don't know. Financially, as I say, the silicon power rectifier. Are you acquainted with this book (points to book case) put out by Bell Laboratories?
Impact. Yes and I should go back and look at it again.
I went through and looked in the index. In '69 the sales of devices on which I hold the patents were eighteen million dollars-worth of thermistors (page 35), 5.8 million of solar batteries, (page 21), 154 million of silicon rectifiers, (page 18), 20 million of field effect transistors (page 19) and 65 million of pnpn devices (page 22), for a total of 260 million; about a quarter of a billion dollars in one year.
What was the immediate stimulus for your honorary doctor of science degree at Willamette University?
The solar battery. It is the most famous development and got all the headlines in the newspapers.
But it isn't what you feel to be your most important contribution?
No, I don't think so.
We were talking about press coverage. When the transistor was announced to the press, it appeared in a single column of about six inches on the obituary page of the NEW YORK TIMES. When the solar cell was announced, it had a big spread on the front page with pictures and a detailed write-up. In fact I was told that this was the best newspaper publicity coverage ever in the history of the Bell System. So that's the reason when they think of Pearson, they think of the solar cell. It is the most important publicity-wise, but I think scientific-wise it may not be. Although as it turned out later when the satellites came along, it was very important. All satellites that go up for more that at least a month have to be powered by solar cells. And there have been thousands of satellites put up which are all solar cell powered. The scientific equipment on the moon and on Mars wouldn't function if it weren't for solar cells.
In late 1959 an industry-university cooperative program of solid state electronics was inaugurated at Stanford and you represented the contribution of Bell Laboratories. Shockley was contributed by the Shockley Transistor Company. Several other individuals were contributed by several other companies. Can you tell me a little more about this?
It is called the Stanford Solid State Industrial Affiliates. And it's a group of industries connected with Stanford and up to this year, each industry contributed $5,000 per year to Stanford. The contribution is now $7,500 per year. We have a meeting once a year where representatives from all these industries come and they meet our students and have the inside track on hiring them. We discuss our publications and thesis and so forth at the meetings. We send copies of all our reprints and these to these people. So it's a close connection between various industries and the solid state section of the Electrical Engineering Department at Stanford.
Who cooked this up?
I think this was cooked up by Fred Terman, who was provost at the time and John Linvill, who is now the chairman of the Electric Engineering Department.
I gather that it is functioning rather well.
We have about 25 or 30 members. And just recently, within the last couple of years, we've added foreign companies. In Japan, for example, we have Sony and Toshiba and Mitsubishi.
Are you aware of anything like this in the United States, or is this effort of Stanford unusual?
There are several others at Stanford. The Chemistry Department has a similar thing. And the Materials Science Department also has one. I'm not acquainted with other universities.
It's a fascinating theme in the history of that part of American science that developed and is developing out of industry.
It's also nice for the professors in that this is unrestricted money. Each professor has one or two or three companies for which he sort of directs the program. That individual professor gets half — gets $2,500 of the $5,000 — to spend as he pleases not to go to an opera or this and that, but for scientific purposes. For example, I'm going to an international conference in Edinburgh next month and then going on to Warsaw where the Polish Physical Society is giving me a medal. The citation is for contributions to science and development of good international relations between American and Polish physicists. This money will pay for my trip.
Do the industries who currently contribute include Bell Laboratories?
After the first five years, they have been contributing. I think it was only during the first five years that we considered them a member without any contribution.
They were contributing your pension money during that early period?
They have contributed pension money since I retired in 1960.
But that they would now be contributing to you anyway. I'm not clear exactly what the industries get back from this.
They get first-hand knowledge of what we're doing. And they get first crack at our graduating students.
Don't you publish freely anyway?
Well, yes, we publish freely, but we don't publish the thesis. They give in great detail what goes on. And the industrial representatives also get a trip to California in September each year to attend the conference, which some people think is a great idea.
I think this is probably a good place to stop taping our conversation. I want to thank you very, very much. I'm sure there are many gaps in this interview that we'll want to fill in one way or another in the future.
Possibly several errors on my part.
That's probably inevitable in all interviews. Thank you very much for this one. It will be useful to me and other historians of American Science.
 "Spontaneous Resistance Fluctuations in Carbon Microphones and Other Granular Resistances,” C.J. Christensen and G.L. Pearson, Bell Sys. Tech. J. 15, 197-223 (1936)
 Physics 6, 6-9 (1935).
 Phys. Rev. 56 (Sept. 1939) p. 471.
 See p. 110 Brattain’s “Genesis of the Transistor,” The Physics Teacher (March 1968). Igon E. Loebner, p. 675 IEEE Trans. On Electron Devices Vol. #7 ED-23
 Igon E. Loebner, p. 675 IEEE Trans. on Electron Devices Vol. #7 ED-23.
 p. 619 in W. Schockley, “The Path to the Conception of the Junction Transistor,” IEEE Transactions on Electron Devices, Vol. ED-23, No. 7 July 1976, pp. 597-620.
 "Single Crystals of Germanium and Silicon — Book to the Transistor and Integrated Circuit" IEEE Trans. Inls 1946 Vol. ED-23, #7
 Phys. Rev. 74, pp. 232-33 (1948)
 G. L. Pearson, "A High Impedance Field-Effect Silicon Transistor," Phys. Rev. 90, 336 (1953)
 Phys. Rev. 80, 846-850 (1950)
 "History of Silicon Solar Cells," IEEE Transaction on Electron Devices. Vol. ED-23 #7, P. 640-643