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Oral History Transcript — Dr. Michael Tinkham

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Interview with Dr. Michael Tinkham
By Katherine Sopka
At Harvard University, Cambridge, MA
January 11, 1977

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Michael Tinkham; January 11, 1977

ABSTRACT: This interview was done in the interest of compiling a history of the Harvard University Physics Department in the mid-20th century. Dr. Tinkham shares his recollections and perspectives on the developments within the department since he arrived there in 1966.

Transcript

Sopka:

This is Katherine Sopka speaking. I am visiting today, January 11, 1977 with Professor Michael Tinkham in the office which he occupies as Chairman of the Physics Department, a post he has held since 1975. In the interest of compiling a History of the Department in recent decades, Professor Tinkham has kindly consented to share with me, today, his recollections and perspectives on developments within the Department since he came to Harvard in 1966. Professor Tinkham, perhaps we can begin by asking you about your pre-Harvard background and about the path which brought you to this Department.

Tinkham:

Well, I think that if I were to trace my personal background prior to coming to Harvard, I would tend to start a long ways back. When I was in High School, I was interested in science. In fact, even in grade school. I think my scientific career began in 2nd grade when I received a chemistry set for Christmas, and I was helped along the way by two uncles who were chemistry professors in a small college in Ohio. My mother and father also had both been in chemistry and physics at college, although we were living on a farm at the time, and so we didn't have too much activity of that sort going on. Anyway, I pursued my scientific interest through grade school and high school, and was "in the Westinghouse Talent Search in 1945. This was at the end of the wartime period, and all of our scientific projects were made using things like cooking tins for chassis for electronic equipment, because we couldn't get the real things, so we were cannibalizing things we could find around the house. Then I spent a year in the Navy in an electronics program and became much more knowledgeable about electronics and was convinced it was an interesting subject. As I went into college, I started out in Ripon College which was in our home town of Ripon, Wisconsin, and that was the college that my parents and my uncles had attended in previous decades. In the summer I was fortunate in being able to get a job in Republic Steel in Canton, Ohio, working with a man who had been a student of one of my uncles in Ohio, and this gave me a little exposure to science in the real world, in a steel mill, and this was interesting. I actually got my one and only patent on the electronic device that I cooked up to facilitate the use of the thermocouples used to measure the temperature of molten steel. I spent three years at Ripon and then transferred to MIT on the combined planofstudy which was quite popular at that time. You spent three years in a liberal arts college, and two at MIT in the undergraduate program. But then my career was slightly modified by the outbreak of the Korean War. Since I was still a Naval Reservist, I was somewhat concerned about being called back to active duty. I converted my Bachelor's Program at MIT to a Master's Program, which I thought might give me a little more defense against being called up, so I became a graduate student before I had my Bachelor's degree, but got the Master's and Bachelor's both in the same year. I stayed on at MIT to do my Ph.D. in microwave spectroscopy with Woody Strandberg there, and when I finished that, I had to make a decision as to whether I would go into industrial research — I had a nice offer from Bell Labs — or whether to go into the academic line which had always appealed to me. I actually had a year's fellowship from the National Science Foundation, which I spent at Oxford doing research with Professor Bleaney on paramagnetic resonance. I was still making up my mind while I spent that year there, but decided in the end to come back to the academic route and accepted a position as a Postdoc at Berkeley with Professors Kip and Kittel, who ran one of the major solidstate physics groups in the country at that time. This was a real turning point in my career, I think, because that gave me my first exposure to a really major effort in solidstate physics, which seemed a very exciting field, on which I had only worked on the fringes at Oxford doing paramagnetic resonance on paramagnetic crystals, a very specialized form of solidstate physics. My time at Berkeley was very exciting. I had always been interested in superconductivity, and this interest was whetted by Charlie Kittel running a seminar on superconductivity in one of the first terms that I was there. In this seminar, he assigned topics to all of us in the solidstate group. I was to give a talk on high frequency properties of superconductors, since I had been working on microwaves and farinfrared which sort of fit into this rubric. In preparing for this I read some of the recent papers and discovered that people were all excited about the possibility that there might be an energy gap which could be found spectroscopically, but that none of the measurements made so far had really been very convincing. Well, this in a sense launched me on my major career, because since then I have been working on superconductivity, basically for the last twenty years: first succeeding in finding this energy gap which people were brooding about at that time, and then following on with other types of superconducting work — D.C. effects, quantum interference, fluctuation effects, non-equilibrium superconductivity. It has been a very exciting field, one which I fell into when I was at Berkeley, and more-or-less moved bodily to Harvard with. Perhaps I should go back a step there. I mentioned coming to Berkeley as a Postdoc. In the second year that I was there I was appointed a Lecturer to give a course in group theory which Bob Karplus was tired of teaching. I had always wished I knew something about group theory, but had never learned it; yet they told me they thought I could handle it if I boned up on it, since I had been using group theory without knowing it in my doctoral thesis and my work at Oxford. So indeed I did spend a very intensive summer reading Wigner's great German classic, Gruppentheorie und ihre Anwendung auf die Quantenmechanik der Atomspektren, and rendered this into a so-called unauthorized translation in the form of lecture notes which I handed out to the class. This went over pretty well, and so I was asked to teach a modern physics course. That went all right too, and they managed to find an Assistant Professor appointment for me the next year, and I was then launched on my regular teaching career. This I followed up the ranks at Berkeley and just basically transferred my situation rather bodily from Berkeley to Harvard when I came here in the summer of 1966. The research work, as I indicated, did not really have any major discontinuity at this point. I continued with superconductivity, and I continued with far-infrared studies with my sort of special slant on it. Of course there were changes when I came here, but they were not really major ones, I would say, in the line of my research work. It might be interesting to comment on the differences or similarities between Harvard physics and Berkeley physics. They certainly are different. They are both topnotch I would say, but at Berkeley the thing that you are impressed with is the size of the Department, the fact that we had perhaps 80 faculty members and maybe 350 graduate students. At the beginning of the term it was customary for the former Chairman, R. T. Birge, to comment on the statistics in the Department. On this occasion he, or perhaps his successor, Helmholz, was commenting on the statistics of the number of graduate students in the Department, and he said he thought the number was 357 +/- 5. I remember some graduate student sitting next to me saying, "There I am, lost in the experimental error." (laughter) Well, when I came to Harvard I was told by Bill Preston that in effect that sort of thing wouldn't happen to me here. The numbers are much smaller, and that means the Department is much more closely knit. For example, here we have our weekly faculty meetings over lunch on Monday, which consume a great deal of time, but they develop a feeling that you actually know your colleagues despite the widely different fields of interest in their research. This develops a different feeling about the Department than in the Berkeley Department, where there were about as many people doing solidstate physics as there are here in the whole Department, so the tendency would be to be absorbed rather completely into the subdepartment with people of similar research interests rather than being involved with the Department as a whole. As I think back to the time when I made the decision to come to Harvard, I think that this was something I anticipated, and one of the reasons that I listed on the plus side for the possibility of the move was the feeling that if I were at a place like Harvard, I would have more occasion to deal with physicists and others who were not as close to my field. I thought it would be a more broadening situation than at Berkeley, where you could so easily spend all your effort just dealing with people who were in your same general field. I think that this by and large has proved to be true. I think that another distinction that one might make between the Departments is that Harvard absolutely expects everyone, whether a student or faculty member, to be excellent. (chuckle) Berkeley tried for the same excellence, but because of the larger number of people involved, one could take more chances; some chances didn't pan out, so that some of the people probably would not have been of the same standard, although there were some who were extremely good there also. In fact, I remember Segrč. He was trying to establish the fact that I had no need to leave Berkeley for Harvard. He said, "Sure at Harvard they may have a greater density of firstrate people, but at Berkeley we've got more of them". (laughter) There is something to that, I suppose, but anyway I have never looked back. I have always thought that the move was a good one, and though I like Berkeley very much, I also like Harvard very much; I think it was probably a good change for me to make to get the stimulus of being in a new environment. Different people, different outlooks. I think the outlook here is a little more theoretical. Right now as Department Chairman you might say I'm fighting that, trying to get more experimental people in the Department, because we are looking forward without any enthusiasm to the retirements before too long of some of our stalwart experimenters like Ramsey and Purcell, and they are going to be hard people to replace. As I read the letters of nomination for various appointments we might make, I am struck by the fact that we are going to have to look for people who will keep us from becoming a theoretical institute, which is one of the things that I think would be a disaster if we went all the way.

Sopka:

Does it feel like in superconductivity you must be involved yourself in both theoretical and experimental aspects of it?

Tinkham:

Oh yes. I think that in any field you have to be involved with both sides really. The question is only to what extent it is possible to really make any significant impact on both sides, because you need to have some appreciation of the theoretical questions to guide the choice of experimental projects that you undertake. In some fields such as highenergy physics, the theoretical work and experimental work are both so demanding in terms of the number of people you are competing with and the size of the groups involved, that it is very difficult for one person to have much effect on both sides. In a subject like superconductivity, or in solidstate physics in general, it is quite possible, in fact, more or less the norm, for a person to do the theory which is directly related to the work that he has done in the lab and to me this is one of the things which makes that kind of physics so satisfying. Many of our students, I think, feel the same way. I usually tell a student that unless he has a real urge, an irrepressible urge, to do particle physics, that he should not rush into it, because it is an extremely competitive field, one which forces a person to specialize into doing theory or doing an experiment as a member of a large group. I don't find this as satisfying and I think that unless you find the subject itself so fascinating that you can't think of doing anything else, you are apt to be more satisfied with your work, working in a field in which you are able to really handle both the theoretical and experimental sides. I have one of these letters that I just referred to, nominations from Charlie Slichter, one of our illustrious alumni, who comments on one of the nominees as a real experimenter as opposed to a theorist who directs experiments. (laughter) I think that's a distinction that is all too telling about many of these cases. Another thing that I think you might be interested in talking a bit about is the question of the Chairmanship, since I now have been the Chairman for a year and a half. How did I get here? Well, I got here more or less the same way you get in the Army. You get a note saying your friends and neighbors (laughter) have chosen you to serve them. Well, in this case, it is my "obedient servant", the Dean, who sort of sifts over the nominations of the various Department members who are all polled, and then makes his choice. As in the filling of the Cabinet posts that is going on now for the Federal Government, the first person asked does not always accept, and the Chairman is the first person that the Dean asks who does accept. Let me put it this way. I think it is the expectation that the majority of the faculty members will serve in some form of rotation. As one can tell simply from the arithmetic if one serves for only three years, and if there are, say, fifteen faculty members and they are typically here for thirty years, it appears that approximately twothirds of them must serve one term. And so, it is somewhat a question of deciding whether a given time is as good a time as ever to do your stint in the job. As you can, perhaps, tell by these remarks, I don't view being Department Chairman as something which I would go out and run an election to get into. (Laughter) It's more a job which is obviously important in terms of getting the Department's business done, but which also takes a lot of time and doesn't necessarily give you the feeling that the time is always being well spent, considering the amount of routine work which has to be done, the number of irreconcilables that have to be somehow reconciled, such as in terms when three people want to teach one course and zero people want to teach the other two courses (laughter), and the endless numbers of questionaires which seem to be produced by the Government, the University, and other universities who seem to take delight in tormenting each other by sending questionnaires about how each other does things. Many of these things require information which you don't have available readily and which has to be developed by searching through files. I certainly wonder if this is really what you should be spending your time doing. It seems to me that my most essential function should be to worry about the future of the Department, and to assure that we seek and find the best faculty members we can to appoint. But, of course, the Department Chairman can only serve as a catalyst and as a secretary for such things. We have to search externally, we have to all pitch in, we can't always find the person we want, and we can't always attract the person we want; so this is the sort of job which goes on and on. If you get a good appointment made, you can consider that a real achievement. If you do not, well, what else is new! If you don't succeed you just have to carry on the search until you have better luck the next time. I have, of course, responsibilities in many directions. I think that what I am serving is "the Department," which is a somewhat elusive term. Is the Department the faculty, or is the Department the students? And there are days when one even has to distinguish between junior faculty and senior faculty. I remember hearing a comment from some of the junior faculty, who felt that they were not being given as much say in various decisions as they might be that they feel that at Harvard the senior faculty were Harvard, whereas the junior faculty worked for Harvard.

Sopka:

That's an interesting distinction.

Tinkham:

And so this perhaps illustrates other kinds of irreconcilables that the Chairman is attempting to reconcile: the needs of the continuing institution, as reflected and seen by the permanent faculty who have been here long enough to see many things come and go, and the responsibility to provide a good working environment for the junior faculty who are here with the full realization that only one in ten, or some such number, will be able to be kept permanently, again just because of the numbers. We have roughly a similar number of junior faculty and of senior faculty, and yet the junior faculty stay typically for five years and the senior faculty stay for thirty years. This means that only one in six could be kept even if we took no senior faculty from outside; since that would, of course, tie our hands on recruitment, in fact, it's only one in ten. So this is just one of the inescapable, numerical situations that we are dealing with in this Department. It means that the junior faculty appointments have to be ones which are attractive in their own right as a vehicle for carrying on research and getting experience in contact with our senior faculty, who are very distinguished in general. This is a package which I think is reasonable. But, needlesstosay, towards the end of each person's career in the junior faculty ranks, when the decision about tenure must be made, it does inevitably bring wrenching and difficult decisions, which in most cases are negative, and it is not one of the more pleasant parts of the Chairman's job (chuckle) to communicate such things. So these are some of my thoughts about the faculty. I have to try to find the best way to use our faculty manpower in teaching courses, the best in the sense that the faculty members can teach courses which they find interesting and stimulating to teach, and yet which also provide the students with the best possible instruction. Luckily, these two desired goals usually are quite parallel; the faculty member who is excited about teaching a course usually will convey this feeling to his students. There is usually no real difficulty except that some courses seem to be more fun to teach than others and tend to have more faculty members interested in doing it. The students, particularly the graduate students, of course, I see a great deal of, because the Chairman not only assigns them their jobs if they are Teaching Fellows, but the Chairman is also the person that has to approve all their oral exam committees and, in many ways, worries about the whole academic experience, whether it's on the side of the teaching or research, employment, fellowships, courses, committees, exams, degrees. You name it. I do it. (chuckle) So I, needless to say, see a lot of the students, and I try to be as responsive as I can to things that they say about the way the Department works, because after all they are our product. I mean, they are the things we are most proud of as they go out into the world. Well, should I state that in a slightly more cautious note? I think that we consider our students our most permanent product, but the research that gets done while the students are here working with us is also in its own right a thing which is certainly an essential product of the Department. Another direction in which I'm responsible, of course, is to the administration, to the Dean, to the President, and this comes in the budgetary field. I have to manage to staff all these courses as efficiently as I can so that I can get the most teaching out of the dollar which they give me. I also have to be sure that any appointment that we try to make is of the highest quality. But the interests of the Dean and of the President and of our Department are again quite parallel; I think that we all want to make the Department as good as it can be. Actually, that triggers another remark in comparison of Harvard and Berkeley. When I came to Harvard with its smaller and more intimate relation between the faculty and the Dean, etc., I really had a different feeling than at Berkeley. At Berkeley you felt that there was much more of a "we" and "they" type situation between the faculty and the Administration, with the Regents and the various political inputs from the State, whereas at Harvard I felt by comparison it was very much a matter that we were all together, and that the Dean indeed was our "obedient servant" (laughter). If there were anything which needed to be done for the benefit of the overall teaching program, the University would in general have resources made available to us.

Sopka:

Do you have to spend much time attending to extra-departmental, more administrative things? I assume you have to represent the Department at the formal Faculty Meetings of the University.

Tinkham:

Oh yes.

Sopka:

Are there other duties?

Tinkham:

That's right. There are a few things like that, and I do have to go to the Faculty Meetings, but that after all is not a big chore. I often went to them beforehand, but certainly not with the regularity that I do now. There are meetings of many sorts that the Department Chairmen get called into to discuss things: ways of raising research funds, new government programs which we might be able to fit into, things of this sort. I have been serving on the Executive Committee of the Materials Research Lab. This is something which I might do just as a physicist, but I notice that two of the other members of this committee are the Chairman of the Chemistry Department and Chairman of the Geology Department, so I suspect that, to some extent, effort has been made to get the Department Chairmen into this just because of their role. They are in touch with many of the things that are going on, and so I can see why Department Chairmen are in demand. If you spend a few years trying to ride herd on a Department, you develop a lot of knowledge of what's going on which should be used in as many ways as it can be. When you add these sorts of things on to the internal chores of running the Department, it does add up to take time. But it's also one of the things that makes the job interesting, so I would, I think, not be too negative on some of this. It's the variety, and the fact that you feel that you are engaged in something which takes you outside the Department, where you help in trying to look out for the Department's interests and the way it relates to other units, etc. It is part of the challenge of the job which goes beyond the sheer minutiae of filling out the questionnaires, etc., so I wouldn't want to knock that very much.

Sopka:

Are you able to do any of your own research and teaching during this period when you are functioning as Department Chairman?

Tinkham:

Well, you might ask my students, I suppose.

Sopka:

Well, I heard your students at the Christmas Party present you with a token of their esteem.

Tinkham:

Yes, well I think that refers more to my dealings with the graduate students in general, trying to be sympathetic to their needs, and trying to be responsive as best as I can. I did appreciate that very much, unexpected as it was, and I have now tasted the Burgundy, and it was indeed delicious. I am still waiting for a suitable occasion to go into the Bordeaux. In my own group, I have continued to have about half a dozen students carrying on research work. This is only really feasible, however, because of the presence of Bill Skocpol on the faculty. He finished his Ph.D. as my student a few years ago and stayed on with the group as an Assistant Professor. We run this group jointly, and needless to say the students see much more of him around the lab than they do of me at this time. It's thanks to his being there that it's more or less possible to keep the research group going with as little attention as I can give it. On the other hand, I do insist upon keeping as closely in touch with it as I can, which I do by two means at least. First, we have a group seminar which meets in my other office, what I call my real office, in Lyman where all my physics books are plus my research administration books. This is a seminar in which all the members of the group including myself and postdocs, etc. speak in strict alphabetical rotation on whatever is currently going on in our research work, or something we have read about, or whatever. This provides a weekly forum in which the group all meets together, and we discuss any common points before having one of the members of the group give a seminar. In this way, every six or eight weeks we make a round with everyone speaking. This is a means for me to keep in touch with what everyone is doing and also it gives me a chance to comment and give suggestions as they occur to me in listening to these talks. Of course, the students all pick on each other very much. It's an interesting format and one which I will say has been one aspect of the way my group works which I have stuck with religiously since I started all those years ago back in Berkeley. A great number of people who are alumni of my group, whether they were post-docs with me or students with me, are now in the position of running their own groups at other universities, all over the world, Japan, Europe, this country, Canada, etc. They often remark to me that one of the things which they have taken away from my group is the tradition of the weekly seminar in which everyone speaks in alphabetical rotation, etc. Apparently this is something which has been effective and has been seen as such and something that I can continue to do even while Chairman, because it does represent a controlled amount of time which I can just set aside from the Chairman's Office. The second way I have kept in touch with my group since coming to Harvard has been by having lunch with my students most every day. This is mostly for social reasons, but we do cover any research topics which seem to be in need of discussion. This again I might comment is a distinction from Berkeley. At Berkeley, it was customary that I would eat lunch every day with the other faculty members in solidstate physics. We would go to the Faculty Club and sit together for lunch. Here, somehow the sociology works a little different, and it seems to me that I am closer to my students instead of to a little group of solidstate physicists as I was in Berkeley.

Sopka:

Do you brown bag the lunches with your students, or do you go to the Science Center, or to the Faculty Club?

Tinkham:

Well, none of the above is correct. We used to go over to Harkness and now go to the snack bar in the Pound Building of the Law School. We find this a little bit more pleasant. We ritually go over there. We just sort of go our own ways and meet there.

Sopka:

The condensation point for the Tinkham group.

Tinkham:

Yes, it's very pleasant. We even have visitors from outside. We can give them a choice of a meal at the Faculty Club or eating with the group at the snack bar. Many of them prefer this, and go along with us, rather than to spend the time going to the Faculty Club.

Sopka:

Your appointment, according to the records, seems to be partly with the Division of Engineering and Applied Physics and partly with the Physics Department. Is that correct?

Tinkham:

Yes. When I was asked to come to Harvard, the appointment that was offered was, indeed, a joint appointment, 5050, between Physics and the Division. I am not fully aware of what all was behind that offer, because needlesstosay, they don't tell you. But there are no other joint appointments of that sort at the present time, although we do have many informal connections with the Division. In fact, at the present time, as undoubtedly is known to you, Professor Martin, who was my predecessor in this office, is now serving as Dean of the Division, and Van Vleck had done so at an earlier time. So there is obviously a close relation, but there have not been other appointments which were made from the beginning as joint appointments. When this offer was made to me, I considered the joint appointment particularly desirable, and I continue to support the idea of joint appointments. I would like to think of making more, perhaps with some of the people who are presently here, to give them formal joint appointments just to cement the close relationship that I think we should have between the two groups of people. My feeling in coming was that there were features about both the Physics Department and the Division which I liked, and I think I felt that the joint appointment enabled me to have the benefits of close association with both of them. Some people look at it the other way. They look more at the things that they don't like about each, and being associated with both. The worst of it, at least to me, is that you have to go to twice as many meetings. But I discovered whereas the Physics Department meets every week for a luncheon meeting, the Division meets about every six weeks for a very short meeting, because the Division, being much more diverse than the Physics Department, just cannot maintain the kind of closely knit structure that we do. As a result, the Dean has to exert more of a leading role, and the faculty can do less in a collective way than we do in Physics. The idea of having meetings to thrash things out is just not as effective in a larger organization as it is in Physics. Now with the new Dean in the Division and with me here, a member of both departments, I do wonder if we shouldn't go further towards, as I said, cementing the relation between the two. At the present time Division Faculty members are teaching in a substantial number of courses with Physics titles, and occasionally Physics Department members teach Division courses, since the courses in solid state physics are historically offered in the Division, whereas the courses in classical physics, quantum mechanics, etc. are traditionally given in the Department. Since we view the teaching, not only the formal teaching, but perhaps more importantly the supervision of graduate students, as very much a shared undertaking, I think that it might be desirable to have the formal structure reflect this. That's why I, personally, would be inclined to see if we can't find a generally acceptable way for creating more joint appointments. These would not necessarily be new appointments, but they could simply acknowledge that some of the present members of the Division teach considerably in the Physics Department, and vice versa. Then these teaching commitments would be formally recorded and would not disappear when there was a change in the administration of the courses. The department Chairman does assign teaching responsibilities in consultation with, and with the agreement of, his faculty, but if my replacement in this office felt less comfortable than I do with the Division, there might be less use of the available faculty from the Division in teaching Physics courses than we have now, and which was started when Martin was Chairman. I think that would just be a loss to the Department and to the Division. A more formal arrangement would make it a little less dependent on the individual initiative of the Chairman.

Sopka:

The Annual Reports that are written by you and the Director of the Laboratories seem to be two sides of the coin of what's going on in Physics today at Harvard. Is that an accurate assessment of the relationship between the two posts?

Tinkham:

Well, I think so. The Laboratory Director is basically responsible for the business sides of the Department: the handling of the special funds, the building, and support staff, whereas the Chairman is responsible for the teaching, the purely academic side. Of course, there are areas in which our responsibilities overlap, and we often try to hash out together what the best thing to do is. For example, when I talked about assigning assistantships, etc. to students for their support, the monies for these things are handled by the Director's Office. We have to be in communication, so that I'm not saying one thing, while he is doing something else. We also confer when we are in the process of hiring nonteaching personnel. For example, with the coming retirement of Frank Robie we'll be looking for a man to take over the general supervision of the building and all that goes on in it. This is something which is obviously primarily in the Director's Office, but since it is something which has such an effect on the teaching and on everyone in the Department, we will be collaborating on the search for a suitable replacement.