Oral History Transcript — Dr. Benjamin Lax
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Benjamin Lax; May 15, 1986
ABSTRACT: Research on the solid-state maser and the semi-conductor maser and laser within the MIT Lincoln Laboratories, 1963.
Lax:[Dr. Lax responds to an off-tape question about discussions with Prof. Nicolaas Bloembergen about the solid-state maser.] He discussed with me, I guess it must have been in 1956, prior, or I think about the time of his publication.
Bromberg:I brought along some of [Bloembergen's] notebook extracts. On the second page of that—those are his notes—and the entry on the [second] page, the first entry says that he talked to you, already, June 1st.
Lax:Yes, I think so. I don't know when we did our maser, but I'll check on it. I should have looked some of this up....
Bromberg:I guess that what I know so far, what I think I know, is that Bloembergen was in touch with you people and at some point in the course of that, maybe in the early fall, I'm not sure, you proposed to Meyer and McWhorter --
Lax:That's correct, I proposed to Meyer and McWhorter, after Bloembergen talking to me, that we work on a maser. In fact, I ordered one of them to quit what he's doing and to do that, McWhorter. He was working on surface physics, and yes, that I recruited him and Jim Meyer to work on the three level maser, that's correct. This was before he actually put it in print, but Bloembergen outlined to me the idea of the three level maser prior to publication.
Bromberg:What was Bloembergen's relation at that point to --
Lax:He was a consultant.
Bromberg:To your group specifically?
Bromberg:The solid state group?
Lax:Yes. That's right.
Bromberg:And how do those consultancies work? Just to give a little background on what was going on, how do you choose a consultant, what do you want from him?
Lax:Well, we picked Bloembergen not because of the maser. We were working on magnetic phenomena, resonance phenomena, which is related to some of those things, and Bloembergen was one of the experts and had done some very interesting experiments with his students, and consequently we chose him as one of our consultants.
Bromberg:I was just wondering how much the very fact that he was a consultant for you disposed him to think about the importance of devices. It was just an idea that occurred to me.
Lax:It may have been. I'm sure his discussions with Zeiger and with Meyer, who was working on his thesis, I'm sure influenced some of his ideas. But certainly I think he deserves the credit for conceiving the particular system. I know that Zeiger had talked about three level systems, prior to our discussion with Bloembergen, but Bloembergen I think put these ideas together. The three level system, to my knowledge, was first suggested to me by Zeiger, but not in a solid.
Bromberg:In a gas?
Lax:In a gas.
Bromberg:Because Javan had also been thinking about three level systems in gases.
Lax:But this goes back I think even prior to '56. I think it goes back to about '55. Zeiger talked to me about a three level system before Bloembergen invented the -- and I don't know whether Zeiger had talked to him prior to that. He may have. And discussed his ideas. But certainly not in a solid. So that's clear. I mean, that idea of a solid state maser is definitely Bloembergen's own idea. But the three level system I think may have pre-dated his concept.
Bromberg:That's very interesting. It makes a lot of sense.
Lax:That's my impression. But I mean, look -- an invention is a synthesis of many people's ideas, as I'll show you on the semiconductor laser. No one had all the pieces together. He put all the pieces together. Just like Einstein. When he discovered, you know, relativity, he took the work of Lorentz and Maxwell and others, and saw relations and things. Some of the concepts were around, but they weren't fully crystallized.
Bromberg:So now we're still talking about this early period when McWorter and Meyer are working on this three level maser at Lincoln Labs, and I'm wondering among other things, Scovil, Feher and Seidel were working at Bell Laboratories. What kinds of contacts, if any, did you have with them? With Bell?
Lax:We didn't have any contacts. My understanding is that they got the information somehow about Bloembergen's concept of a three level maser, which was theoretical at the moment, and Bloembergen suggested to us that we work on something, and he knew that Meyer was working on paramagnetic resonance, and I wanted to put a team together to work on this. We didn't know anything about the Bell group. In fact, we picked our own crystal, which was an entirely different from theirs, and we grew our own crystals. Dr. Harry Gatos grew potassium chromicyanide. It was the first time that chromium was introduced into a maser, and even before ruby, and that, to my knowledge, was a first. The system at Bell Telephone was different. So the work was done independently but I believe that the Bell people got there first.
Bromberg:Was that a surprise, when they…?
Lax:No, because I think they were more experienced. We were just beginning. McWhorter had not done this kind of work. The only man doing paramagnetic resonance and microwave work in the group was Meyer, that's why I selected him.
Bromberg:Was this a fairly new group at Lincoln? You become head of the group in '55.
Bromberg:Was that when it was formed or was it already an old established…?
Lax:Well, the group was established earlier. The group started in 1951-52 and I was one of the original members. Then I formed my own group, on ferrites, which was microwave resonance techniques. In fact, in '53 I was doing cyclotron resonance. So I was very successful with that and they appointed me the group leader of this larger group, and we merged, so that it wasn't a new group, but the idea of working on the maser originated with this conversation with Bloembergen, and I decided it looked like a good idea, let's work on it.
Bromberg:Then after that was there much that went on with masers in your group?
Lax:Yes. Dr. Kingston took the maser, and put it on a radar. In fact, we were the first to put a maser on a radar, and I believe it was used to get a signal either from Venus or the moon, I don't remember, but from a planet. There was a microwave radar.
Bromberg:Now, Lincoln was funded by the Air Force, isn't that right?
Bromberg:What was the relationship between Air Force and what the actual scientists were doing? You were group leader, then you were division leader, so if there was an interface it might have been you. What went on in that kind of…?
Lax:Well, let's say, we had regular meetings with the Air Force, but essentially as group leader I interpreted what our mission was. In other words, our mission really was to try to develop devices that relate to radar and microwave technology at the time, or let's say computer technologies. So that's the way I interpreted it. What we would do would be, somebody would come up with a good idea. Sometimes it was myself, sometimes it was someone else, and they would propose it. In other words, we would ourselves initiate and identify, and we recognized what the context of the research was. In those days, I'm happy to say, there was much more freedom and leeway, and the balance between basic and applied research and their interaction I think was much more -- well, much more synergistic. And there was room for a broader spectrum of activity than today, say, at Lincoln.
Bromberg:We talk to a spectrum of people and we talk to a lot of people who are scientists within the group, but they in particular don't have the vision I think that people who are at higher administrative levels have of what the relation between context and work is, and that's why I'm particularly interested to see how you worked. How you structured --
Lax:Well, there aren't too many people who have vision, and who see these relations. In fact -- my feeling is, a lot of people are very myopic. In those days I think things were a little bit different, and some of us have it, some of us don't. And I'm happy to say I've been very fortunate in that regard.
Bromberg:That's very good for me. I want as much as you can remember of how you were thinking in those days, in this respect, and how it might have changed with one or another project, or with the years, or --
Lax:In fact, what things we worked on really depended on just a handful of people, which I call the creative key people, and in my group, I happened to appoint them usually as group leaders, although in the case of people like Zeiger, he didn't become a group leader, later, but he was a creative fellow and McWorter was a creative man, Harry Gatos, and these people were both intellectual and personal leaders. And there were others besides them. But as I said, it amounted to maybe a handful of these people, and we were the ones who came up with ideas. There was a free discussion between individuals, and people would come up with suggestions, and that's how we formulated the program. But we were aware of the broader context. I probably had more, let's say, influence and certainly, being the Division head I had to approve these ideas and projects, if they required resources. But I also had radar experience, and so therefore I could relate these things much more to the overall requirements. I still do. I'm going back to Lincoln, now that I'm retiring, to do just precisely that sort of thing, in laser radar. So some of us have had that fortunate experience of working in the Radiation Laboratory, Lincoln Laboratory, where we can see the relationship between basic and applied science and engineering.
Bromberg:Do you recall what the big projects were in applied science at that point? I was just reading some articles by John Pierce, and clearly right through that period he was thinking about the need for transatlantic communications and the possibilities of satellite research. He was thinking of satellite communications, thinking of that before -- and after -- the maser. I'm just wondering if you recall what might have been the big needs of that time?
Lax:In our particular context of Lincoln Laboratory, the two major areas, well, three major areas were communications, radar, and computers, and we were pioneers in all three of these, so that certainly anything that had to do with communication receivers, sensitive receivers, and in the context of radar -- and we had a group that was doing planetary radar, developing techniques which later -- although they appeared to be sort of basic research in astronomy, they turned out to be very important for present day planetary and space science. So we had need for more sensitive receivers, although I think people like Bloembergen had it in the context of astronomy, rather than radar, but we reorganized its usefulness in radar.
Bromberg:OK. Now, was the traveling wave maser much worked on at Lincoln?
Lax:No, we didn't work on that. That was strictly I think the Bell people.
Bromberg:Because McWhorter mentioned that he tried at some point with Meyer to build one, but I have no idea how --
Lax:Well, as far as I know we didn't accomplish much there, even if we worked on it. You mentioned in here question 4, research on noise. McWhorter was an expert on that. In fact he did his thesis in that area, and I think one of the things he did measure was the noise in the maser itself. So that was I think in addition to building one of the first successful masers, I think their work on the measurement of noise was rather significant.
Bromberg:One of the things I've been trying to get some feeling on -- very shortly after masers began to be developed, parametric amplifiers are developed, and I'm always wondering how those things --
Lax:They were independent. In fact, the parametric amplifier actually came out of work on the ferrites, with Harry Suhl at Bell Telephone. He suggested that. That did not turn out to be a very useful device in terms of practical engineering, but nevertheless that stimulated people to think about other nonlinear effects which might work, and the semiconductor parametric work ultimately, and I don't remember who thought of it, but certainly I know we weren't the first to think of it, but people like Kingston and others at the Lab decided they wanted to work on that, and that was perfectly fine, and it turned out to be a more practical device, although not as sensitive as the maser. So consequently we worked on that.
Bromberg:I see, so that also became part of --
Lax:That's right. That fits into the main stream, whatever we worked on had to have some relevance to the radar and communications systems which we were working on at the Lincoln Laboratory.
Bromberg:I see. That's something that I didn't realize. I have had the feeling that you could do anything at Lincoln as long as it was some use to the general electronics community.
Lax:That's true. That's true, it didn't necessarily have to -- but these two things had an immediate relevance and application.
Bromberg:Later on I'll ask you what kinds of documents to look into to find out how decisions were made and that kind of thing on program. Now, I asked you question 6 already, in fact.
Lax:Well, I think our function was -- let me put it this way: the way we interacted with the Air Force, we met regularly with them on a formal basis twice a year. We presented our program and they reviewed it. And apparently they were extremely happy with what Division 8, the solid state division, was doing. That's why I got promoted more quickly than I anticipated on several occasions, because I think we were doing just what they wanted us to do. And so, our work was well received, and I must say that the Air Force, from my point of view at that time, turned out to be a very intelligent and receptive sponsor.
Bromberg:Were there good people there in the fifties?
Lax:I think so. There were good people, both in uniform and in the civilian component of the Air Force. I found the Air Force to be a very good sponsor.
Bromberg:Would that be OSR dealing with you?
Lax:No. Well, OSR was one component, but no, we had several, we had people from different portions of the Air Force. We had them from AFCRL. We had them from Wright Field. We had them from all over, as well as headquarters. So it was a multicomponent representation, and there were other services there, but I would say our major interaction and responsibility was to the Air Force.
Bromberg:What kinds of interaction were you having with firms like Hughes, Bell, Westinghouse, or the other government labs? Was that a big factor?
Lax:No, except we all met at meetings, and were aware of each other's work through the meetings and followed the publications, formal or informal. Sometimes we got to review their papers, for publication. But I think most of the interaction was through the special and the general meetings.
Bromberg:You weren't reviewing proposals for the Air Force? Some of these were big defense contractors.
Lax:No, we did not. We had no responsibility there.
Bromberg:Or no special relation to them because they were sometimes big defense contractors?
Lax:No, I think it was our personal relation. I don't know whether it's still true, I'm sure it is, but the community was very friendly and interacted, especially at meetings, not only listening to the formal papers but we had a lot of discussions outside in the hall, or we'd go out to dinner together, and so a lot of information was passed during those meetings.
Bromberg:OK. We can start talking about the early beginnings of the semiconductor maser, I think, semiconductor laser, it was really both as you began to think about it.
Lax:[Reading the list of questions] You're asking me for recollections of Lincoln Lab maser moon and Venus shots -- yes, I think I said yes, I have recollections. We had the millimeter wave program of Foner [?]; that came out as a natural thing. We built pulse magnets to do cyclotron resonance, and so we used these to push the maser to the millimeter. You asked me if my first notebook entry on semiconductor masers was dated '57. I tried to find that. I don't know where that is, but I know it's in a notebook. I saw it a year or two ago. I looked for it yesterday at home and I don't know where I put it. But I know that's true, and I know the circumstances, because I found some information in this book on it,  things that I didn't realize I had even published then. In fact, it says -- in fact I have the references here. I got the idea about working on a semiconductor maser, even the first basic concept, through a presentation that Pierre Aigrain gave here in '57 at MIT, about using germanium as a semiconductor [maser?], and apparently, Zeiger and I independently concluded, this came up later when we talked, independently concluded that germanium wouldn't work because it was an indirect transition material. Zeiger and I talked a great deal about these things in those days. And we didn't think it would work. And we thought that a direct transition -- because I was studying the optical and magneto optical properties, and we understood the difference between say something like germanium, and the intermetallic compounds, like gallium arsenide and indium antimonide. In fact, indium antimonide was my candidate initially. Later on it turned out if we had done that, we would have had it earlier, but that's another story.
Bromberg:Yes. I wonder if there's any record of that?
Lax:Well, there is a record. I didn't find it here, but there's a record. In fact, the reference that I gave here is the International Conference in 1958 in Brussels.
Bromberg:Yes, I know that, by the way --
Lax:But I heard him [Aigrain] talk on this before that, here.
Bromberg:I know, that's interesting, because I heard about the Brussels Conference but I didn't know about the earlier one. I just want to tell the tape recorder what we're talking about here is Professor Lax's article in the Schawanga Lodge Quantum Electronics Volume.
Lax:And there I definitely, I think I was the first one in print to say, the last sentence on page 444,  "a direct transition is… can be utilized in a more efficient system, since the probability is usually many orders of magnitude higher -- it is just a question of finding the suitable materials." In other words, I was thinking as I said about the III-V compounds at the time. I may even have mentioned it earlier. Luminescence had been observed in '55, by Bravnstein.
Bromberg:I see. That's very interesting, because I had just assumed that nobody much was speaking about the compound semiconductors before 1961.
Lax:No, I say it here. I say it here. As I said, I wasn't specific, purposely. In fact we were trying to keep some of this under our hats, with the intention of working on it. We didn't do it, even though '59 I published this, I didn't make a decision to work on it I think until '60 or '61, when I specifically called Keyes and Rediker into my office and I said, "We're going to work on this."
Bromberg:At this point you are also on the committee for the conference. You're a member of the organizing committee of the conference.
Bromberg:How did that play or not play into all of this stuff?
Lax:Nobody was asked to speak on semiconductor lasers. In fact, Townes asked me to do it. And so I talked about the things that were closest to me, and I talked much less about this, as I said, on purpose, because I kind of felt this was the approach, even though I made this remark.
Bromberg:Did you begin to think about cyclotron resonance lasers after Townes asked you to speak? Was that done sort of to meet the needs of the conference, or…?
Lax:I'm not sure. I'm not sure. It may have been coincidental. I probably had been thinking about it. Actually the cyclotron resonance maser—and I seem to imply it in here, after I did this thinking and study -- in retrospect, and I think possibly even at the time, it was not the best candidate. In fact, I never considered seriously working on it, because I believe I came to the conclusion at the time that that was much more difficult.
Bromberg:So here you are at Lincoln and you were thinking about this and talking to Zeiger. Was anybody else involved in this?
Lax:Well, Zeiger and Autler were talking about, I don't know whether it was later, I guess it was about this time, Zeiger, Autler and also Basov and others were talking about using p-n junctions. I wasn't very excited about that. I think Basov and co-workers were talking about avalanche breakdown. That didn't excite me either. And it was I think subsequent, that was afterwards -- as I said, the ideas were not crystallized, neither as to the material nor the method. But in 1960, they were. In my mind anyway.
Bromberg:How did that happen?
Lax:Well, a number of things. First of all, I think Maiman's laser influenced me, and I started thinking about optical pumping. Furthermore, I was also doing the magnetic resonance, and realized that optical pumping and indium antimonide at low temperatures in a magnetic field, would be the best semiconductor laser, and when we first met in my office with Keyes and Rediker, I think it was in 1960, either the latter part of '60 or early part of '61, we argued about it. I wanted to do it optically pumped, they wanted to do with a p-n junction, which I think, the idea originated with Autler and Zeiger, and so, I gave in, which, to be honest with you, was a mistake, but I didn't have manpower to put on both approaches. However, I did agree with them that I thought, if they could make that work, that would be a better approach, more practical. The other turned out to be easier when we did get around to it.
Bromberg:By the way, were you also doing experiments at this point, or you were just a theoretician?
Lax:Well, I'm not really a theoretician, I'm an experimentalist, but who does theory, so I conceived the experiments, conceived the ideas, and I stimulated a lot of other people. (off tape) We argued, and I gave in to them, and I said, "OK, you fellows are going to do the work, go ahead." So they started with the indium antimonide. They couldn't make a good junction. That went on for almost a year, I think. But then we had very good materials under Harry Gatos in gallium arsenide, and they decided to switch and do gallium arsenide.
Bromberg:Because of course gallium arsenide is what they were publishing on, but not on lasers.
Lax:No, that work was intended to go to the laser. We weren't playing around, we were aiming for the laser. And one of the first things they did was to put it at low temperatures, and they saw the enhanced emission, which now in retrospect we understand from the work of Bernard, Duraffourg, in France, in fact I just lectured on it yesterday, why that would work better. But they did this empirically as experimentalists. And then we knew we were going to get a laser. In fact, I showed it to Charlie Townes in spring of '62, I said, "We're going to get a laser in the near future." And then Rediker and company tried to get things polished outside to make parallel surfaces, on these small crystals. We weren't very successful. And time went on. The summer dragged on. And then I got very impatient, although I was going to let them, it was their baby because that's what they started, I personally took charge of it and told them, "Forget it, we're going to do the polishing, now let's get busy. It's going to slip out of our hands." I didn't know at the time that other people were working on it, but I suspected it, because we had published the work of Keyes and Quist on enhanced emission at liquid N2 temperature. It was obvious to everyone who was in the game that this thing would lase.
Bromberg:That was the Durham New Hampshire Conference, wasn't it, that was about July, '62?
Lax:Yes, I think that IBM told us they were interested, and that's when I got panicky.
Bromberg:I see, IBM? Because RCA is the people who also reported there, Pancove.
Lax:Possibly, but it was the IBM people who told me they were working on it. I didn't know that GE was working on it. I had no idea.
Bromberg:I see. Were you much in touch with [Rolf] Landauer, for example?
Lax:I don't know who was it who told me, mentioned it. It may not have been Landauer. It may have been someone else.
Bromberg:Landauer, there was Nathan, there was Lasher, a whole bunch of people.
Lax:That's right, so I didn't know who was working on it, but somebody said they think they were going to get it, so I got panicky. But in the meantime, Zeiger, McWhorter and I were working on the theory.
Bromberg:I see, so that theoretical paper dates back even before the first --
Lax:I think it was. Well, it was done during this time. I mean, we were working on it in the summer of that year.
Bromberg:Well, that's really very interesting. One of the things I'd really love to get is some information on this early -- you know, as far as the world's concerned, this all burst out into the open around spring of '62, and it would be really wonderful for the history project if --
Lax:-- we got the patent because we had bits and pieces over a period of four years. Unfortunately, the pieces, you know, there were missing pieces and things were not fully crystallized. Had they been, I mean, we would have written a paper. But I must admit, recognizing that other people were going to benefit from our work spurred us on to work much more feverishly during that summer. And unfortunately, even though we did the key work, I think we all published within one month of one another, we came out third. But actually I think it was our work, the work of Quist and Keyes, on that low temperature, that, I think, paved the way, and stimulated the others to do it. So the spring of '62 was key to this.
Bromberg:OK, I'm assuming that all the time, the management—let's see, at this point you were head of the solid state division, weren't you by now?
Bromberg:And you were for this of course, you started it and the management I'm sure was all very happy --
Lax:No, we didn't even tell management. The decision was mine. In other words, I made a decision, this is what we're going to do.
Bromberg:That's interesting too. Does that reflect on the structure of Lincoln, that once you get to the top of the division, there's nothing you have to clear with anyone?
Lax:Well, it was always my style. And I think I was allowed to do it because I guess I had accomplished certain things, and I assumed that was part of my job.
Bromberg:That's what I'm trying to get at of course, the way in which these things were happening. Were you in much touch with people like Bernard and Duraffourg?
Lax:No. No, as far as I -- well, Basov, yes, but I didn't have much discussion with Basov on the semiconductor laser. I think most of our discussions were internal, and we were trying to keep it hush hush amongst ourselves.
Bromberg:OK. So what about von Neumann, does he enter into your…?
Lax:No. No. No, I never knew von Neumann's work. I don't even know now what he did.
Bromberg:I once saw a reference to a man named Richard Seed of the Air Force Cambridge Research Laboratory working on semiconductor lasers. I wondered if that name…?
Lax:No. No, it doesn't strike me. I certainly had no contact with him.
Bromberg:Then what follow-up work should we be talking about? What should we be talking about in terms of the theoretical paper that you did on guiding?
Lax:Well, the theoretical paper I think went independently or in parallel with the experimental work. I'm not sure one had too much to do with the other.
Bromberg:Was this a very surprising thing, this kind of wave guiding along the transition layer? Or what was the point of novelty here that one should understand?
Lax:Well, in fact, I'm not sure we explained that quite accurately at the time. Now that I've been lecturing on it, I'm convinced that, in fact, subsequently when I had some students who were working on it in the sixties with me, I came to the conclusion that none of us had the best possible explanation. We made the assumption that there was wave guiding, but I don't think we justified that, and it was correct. But we didn't justify it for the proper reasons. Now we know a lot more. In fact, a full explanation I think, -- there are a lot of people who don't understand it even now. I do believe that there are some fine points here that are much better understood now in retrospect, and I'd say, even as recently as some of the work in the late seventies and early eighties. But the fact that there was wave guiding, we understood the principle, but the reasons given for it, either by the Bell group, Yariv, and ourselves, may not have been fully correct.
Bromberg:I see, this business of dielectric --
Lax:That's right. I can now go into a lot of reasons why it happens. There were several effects that contributed to that, and we had only accounted for one, which may not have been the major effect.
Bromberg:Did you continue working on that? What happened after '62?
Lax:Well, my original idea of doing the magneto-optical laser, which I thought was a better way to go, we did do, and it worked like a charm.
Bromberg:This I don't understand, you mean optical pumping or what?
Lax:First of all, putting an magnetic field on indium antimonide lowers the threshold, makes it easier. And using optical pumping, you don't have to make a junction, you just simply polish the surface, maybe etch it, and just put a flashlamp, which is what we did, and which is what I had in mind -- of course later on people put lasers on it. I didn't think of that, unfortunately, and I thought the ruby laser would have been an ideal pump, because you could have focused it, and it would have had all the power you needed to make it lase. But when we did it, even with the flash lamp, it worked. And the magnetic effect indeed lowered the threshold, and I had a student do a theory subsequently on that, and we explained the experimental effect.
Bromberg:Did that also turn out to have specific applications?
Lax:No, it's just another variation on the basic phenomenon. But from my point of view, it would have been an easier laser, and it would have required less technology to do it.
Bromberg:You know, all of this provides a much more, a much richer background for what happened. You know how these things get simplified, in the literature.
Lax:And many of the facts are not known.
Bromberg:That's right, I think so.
Lax:And sometimes are not believed.
Bromberg:That brings me to my next question. I'd like to leave you with a very clear idea of what documentation might be around that we should be able to look at and that historians would want to look at and really see how things developed in the field. You talked about your notebooks… [Pause in taping]
Lax:… [Further work on the] semiconductor diode business. We took it and we did it in other materials, the low gap materials, some of which have become in the infra-red. We did a lot of research, both experiment and theory. We did electron beam pumping. And work is still continuing, so I think we were one of the most active research groups and probably contributed significantly in that area.
Bromberg:That question that you're now reading piqued my curiosity. I only got this bibliography last week and I only looked at a few things, but I thought it was interesting, your making that comment that you didn't think the support that was being given to laser work was all that carefully thought through by the services, and I was curious --
Lax:Oh, I think this is true of a lot of our research in this country. I mean, of course, some of that is in some ways fortunate. Some of it is not. In some areas, in some contexts, it's not good. We don't plan science in this country, I think, purposefully. In some areas, maybe, but certainly not in some of these. There are so many organizations, both sponsors, industries -- in other words, it's a random and anarchic process, and some of that is beneficial, some of it is not good. Because certainly especially today, I think the sponsors sponsor things they understand rather than the novel things. In other words, I don't think people have the liberty to take risks the way I had the opportunity to do at Lincoln. I can't do it today. I have to write a proposal on everything. There at Lincoln, I had the resources there. If I heard of a good idea or I thought of a good idea and decided it was worth going after, we did it. We didn't have to write proposals. Today you write a proposal and most sponsors don't understand what you're getting at, and sometimes those ideas are not necessarily well crystallized, as the semiconductor laser is a perfect example. When I first thought of it, I don't think we knew exactly how we were going to go about it. I found a Radiation Lab environment and the Lincoln environment, where there was a fair amount of money, a very fertile environment for starting things. Even bootlegging things, because we had resources, we had people, and if you're in charge you can say, "Well, I can spare a couple of guys" and let them do this work.
Bromberg:This criticism you made of the way the DOD was supporting [lasers].
Lax:Not just the DOD, I think it's a general criticism. No, at that time, it was aimed at something specific. I was part of I think the JASON committee, during that summer, and we were talking about supporting research. In fact, I believe at the time we were considering the weapon possibilities.
Lax:Yes, and the conclusion was, it was not feasible at the time. However, the idea came up that one of the government laboratories should undertake doing the laser research under an organized—you know, in a critical mass -- and my argument was, although it's not possible, you don't know what new developments there might come that might have other applications, and I was thinking particularly of laser radar at the time. And I mentioned it when we were in Washington. Sherwin was the chairman. He's the guy who wrote PROJECT HINDSIGHT, which was a very unfortunate report, I mean, unfortunate comment, and I said, "You don't know what kind of breakthrough might come through that would put an entirely new perspective on it" and sure enough, a year later or within a year the CO2 laser came along, and what I had in mind was the idea that this kind of research prospers and works better under this kind of climate. By the way, we're doing some of that kind of thing on SDI. Things which we should have been doing even if SDI wasn't conceived. But there's more money now, so you're going to do research on components for laser radar, for which you didn't have money before. So what I'm saying is, often in an environment like Bell Telephone Laboratories, where there are lots of resources and there are resources in terms of people and funds, and you have an overall objective, let's say it's lasers or it's something else, you have a greater opportunity and flexibility to do it than if you have to do it on these small scale efforts. You know, university efforts are fine, but I think they have some limitations.
Bromberg:I see, so --
Lax:On the other hand, they do come up with highly original ideas. You know, Bloembergen who conceived the maser, at that time wasn't in a position technologically to build it.
Bromberg:I see. And of course my last question really is related to that, because I was wondering, you were on JASON and you were probably on some other committees that might have interacted with your appreciation of what needed to be done or whatever. I wonder if any of them were of particular importance? Now, of course, this is not a classified interview. We can always run a classified interview if you want to.
Lax:No, I don't want to. I would rather not.
Bromberg:OK. To the extent that you can comment.
Lax:-- not that I'm not working on classified. I am at Lincoln working on classified work, but I would rather not discuss it.
Bromberg:OK. (…) That of course is a very important part of the context, this movement between military and non-military research in lasers is important for lasers. And masers.
Lax:And also I think important, at least in my experience, particularly I would say at Lincoln Laboratory and also I think at Radiation Laboratory, I think there has been a tremendous fallout both for the scientific and the commercial communities, and I will say that some of the best research that has benefitted us commercially I think was sponsored by the DOD.
Bromberg:Yes, there's a fallout and there's also an input into, I mean, they're all very closely tied, and of course historians—what the historians are going to want to do is get at the nitty gritty of some of the ties, because that's so characteristic of what science has been like in this period, that that's one of the things they're going to try to pull out of it. Well, thank you very much.
B. Lax, "Cyclotron Resonance and Impurity Levels in Semiconductors," in Charles H. Townes, ed. Quantum Electronics: A Symposium (NY: Columbia University Press, 1960) 428-449.
"It is conceivable that similar recombination processes across the gap where a direct transition is involved can be utilized in a more efficient system since the probability is usually many orders of magnitude higher. Perhaps it is just a question of finding a suitable material."