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A remembrance
of John Hulm I first met John in the fall of 1957 when he was manager of the "Superconductivity" department at the Westinghouse Research Laboratory in Churchill. He interviewed me for a job with his group that I was fortunate to obtain and joined the labs in November of 1957. Since that time, over the years, we have always maintained a strong relationship both as a colleague and friend and I have personally benefited and enjoyed this long association. I could go on and on with numerous stories about John and his scientific contributions and his many "other" sides but time would not allow this. You might not know this but John has already provided us with an excellent "autobiography" of his scientific career that covers the period from his high school education, higher education at Cambridge University, and his scientific activities and colleagues up to 1982. This after dinner talk was presented at the 1982 Applied Superconductivity Conference and was published in the IEEE Trans. on Magnetics, Volume Mag-19, pp 161-166. I have read and reread this excellent talk on many an occasion and have always been fascinated and amused with the description of his career. In his talk, John identified almost all of the key scientists and close friends he knew that impacted his own career and thinking during that period. I remember sitting at the table in Knoxville listening to John's talk and one of our mutual friends, Bob Hein, leaned over and said, "You are honored, John mentioned your name". I indeed was honored because I recognized it was certainly a tribute that I highly appreciated. John's reference was to the work we did on studying the superconducting transition metal alloys. I would like to believe, partly because I was heavily involved, that this was the most important work we ever did. These transition metal alloys turned out, with further development, to be possibly the most important superconductors for magnets and power applications due to their low cost and ability to carry high currents in high magnetic fields. None of you could possibly believe how the research on the most important alloy Nb-Ti was eventually focused. John burst into the lab one afternoon, walked over to the chalk board, turned around, and stated that we had to study the Nb-Ti system. I said, why, we have already studied Ti-V, Nb-Zr, and Nb-Hf that are all very similar. Because, John answered after going back to the chalk board and diagramming the alloy combinations we had studied, "With Nb-Ti, we would have, God rest the Queen, the Union Jack". Needless to say with that overwhelming argument we went on to study Nb-Ti that just happened to be the most important commercial superconductor of all the transition metal alloys. Such was the persona of John, an excellent scientist, an exceptional manager and administrator, and most important a person who enjoyed life and took pleasure with his many associates and activities. We have truly lost one of the great scientists in the field of superconductivity and I personally will forever be touched by the privilege of his friendship and association. John
Hulm — Scientist and Friend
John's scientific achievements are too numerous to dwell on here. He pioneered in opening the field of semiconducting superconductors, a still active field. His investigations of transition metal alloys formed the body of knowledge needed for the construction of superconducting magnets, which are an essential component of the widely used nuclear magnetic resonance imaging (MRI) systems. He led the group at Westinghouse that made important advances made in developing superconducting magnet technology. The many MRI scans that John must have had after his stroke, in some wry prophetic sense, are the coming back of some bread that he cast upon the water. Unfortunately the further research needed to develop techniques for restoring damaged nerves is yet to be done. It was always fun to travel with John. His knowledge of history-particularly English history and his classical education provided a constant supply of interesting facts, witticisms and wry humor. He was a loyal American with roots that extended firmly back to his English/Cambridge upbringing. He had a passion for railroads probably dating from his childhood days when his father worked for the British rail system. These roots proved to be of practical value to me when I met him at his Auntie's house in London when he was Scientific Attaché to the U.S. Embassy. We were headed to a visit to a national laboratory in Germany when suddenly I remembered that I had left my passport in Cambridge. John, his father's son, called the British railways and arranged for Frances, my wife, to hand the passport over to the conductor on the next train from Cambridge to London where the conductor handed it to us in time make our flight to the continent. After I left Bell to go to Stanford our relationship continued as strong as ever. We jointly wrote papers and organized meetings. John became research director at Westinghouse. I was called in as a consultant for several years. It was a treat to stay with the Hulms, and enjoy Joan's hospitality and to see the growing and active children. I cannot forget one warm summer night when we sat outdoors consuming generous portions of a huge wheel of Stilton cheese that John had especially imported, with beer, and lots discussion on the latest books he had read, and which reflected his fiscal conservatism. John was highly respected for his scientific wisdom and his administrative fairness and honesty. These attributes along with his clear-headed thinking were recognized by the Westinghouse executives who appointed him the Chief Scientist of the laboratory. John lives on as an unforgettable human being in my mind and I would guess in the minds of many. Alas, those glory days of research at Westinghouse with outstanding scientists gathered by Zener and Condon and others, and continued under Chief Scientist John Hulm, live on only in memory. I could say the equivalent things about Bell Labs as well. I am grateful that he, and I too, were there during those golden days. Superconductivity Research In The Good Old Days J. K. Hulm A talk given at the banquet of the Applied Superconductivity Conference, Knoxville, Tennessee, December 1, 1982. One of the most profound statements I ever heard was made by Sam Goldwyn, the movie producer, who said, "I drink to make my friends more interesting." I'm counting on the Goldwyn effect to get me through this evening. If you should happen to be stone cold sober, it might be best to leave right now. I won't be offended. Just don't plan on working for Westinghouse in the near future. I want to thank our program chairman [David Larbalestier] for those kind introductory remarks. I think I need equal time to tell my side of the story.
One day in 1975, I was sitting inmy office in the American Embassy in Grosvenor Square, London, thinking great diplomatic thoughts, when the phone rang and a booming voice came on the line, my old friend Roger Boom, from Wisconsin. Roger said, "Wake up, John, it's time you did something for the taxpayers. I've got this great English superconducting materials guy lined up for a job at our place, but the State Dept. is delaying his visa. Can't you do something?" I said, "What's his name?" Roger said, "Larbalestier." I said, "Are you sure you've got the right country?" Roger said, "Yes, of course I am — he works at Harwell and I need your help, it's holding up all our projects." Well, it was fortuitous that being an ex-immigrant, I had already established my own immigration policy for the U.S. It has always struck me as being ludicrous that we have at least 10 million illegal aliens in the United States and yet in recent years we make it difficult for outstanding scientists and engineers to come here. The official policy is enforced by erecting paperwork barriers which produce endless delays in processing the visa. Well, I applied my superconducting knowledge to short-circuit this process, plus a little hospitality to members of the visa section, and David was one of several outstanding people whose visas got speeded up. It was probably the most important thing I did in the diplomatic service. I became even more convinced of that when I met David's charming wife later on. I want to assure you that they are both here on a completely legal basis. Having been program chairman of the 1972 Applied Superconductivity Conference, I know that it's a lot of hard work. Therefore I'd like to personally thank David Larbalestier for arranging an outstanding technical program for the 1982 conference, and I would like it very much if you would join me for a moment to thank him. It seems to me that the greatest burden of all has fallen upon our conference chairman, namely, Martin Lubell. Perhaps many of you are not aware that Martin worked for an extended period at the Westinghouse Research Laboratories, and, surprisingly, emerged with a completely undamaged intellect. I suspect that he does not know that we at Westinghouse hold him up as an example as one of our more distinguished alumni. What we taught him at Westinghouse about spending large sums of money on superconducting magnet development proved to be but a prelude to the virtuoso performance which he has exhibited since he has progressed towards the senior management levels of Oak Ridge. But seriously, Martin has had a distinguished career in the science and technology of superconducting magnets. He has also worked very hard on the organization of this conference. I think it would be a nice gesture to offer him a vote of thanks at this point for his excellent work as chairman of the conference. Would you please join me in doing that? I cannot resist the temptation to reveal a further piece of data about the Lubell family. Probably a few of you know that Martin's charming wife, Bernie, who is one of the organizers of the guest program, is also a Westinghouse graduate. As a matter of fact, Bernie was my secretary for about four years before I gave her permission to marry Martin. She was a great secretary, absolutely fantastic. As a matter of fact, she ran the cryogenics group with an iron hand, leaving me free to mess around in the lab all day. It was a sad day when this ideal arrangement ended, but I figured Martin's need was greater than mine and after all, man does not live by superconductivity alone. Now when Martin called me in the summer and asked me to give this speech, he suggested that I talk about earlier days in superconductivity research and, in particular, about some of the famous people I've known, such as Bernd Matthias. I thought it would be fun to give such a talk. In the past I have given chiefly technical talks, but this is getting increasingly difficult to do, because I became a research administrator several years ago, and I have to worry more about money and personnel than about real technical details of the research. So I thought, well, I'll give it a try. People often say that it's O.K. to be smart, but it's much better to be lucky. I think this certainly applies to my career. I was fortunate in many respects. In the first place, I entered superconductivity when the field was a relatively small but exciting area of pure science, and when there were some excellent opportunities for basic discoveries. Furthermore, I have witnessed the fascinating progress of the field from pure science to advanced technology. As I stood in the Large Coil Test Facility at Oak Ridge last Monday, I thought to myself, "Who could have forecast such an amazing engineering development, even thirty years ago?" In the language of the advertising world, "We've come a long way, baby" — and we really have. And most exciting, the new NMR scanners are opening up an entirely new field of applications for superconductors. I'm delighted for all our friends in the small, struggling superconductor companies. Hopefully many of them will greatly benefit from this new development and will be recompensed for their efforts as entrepreneurs. The second respect in which I believe my luck was phenomenal is that, with hardly any forethought, but more or less by pure blind chance, I managed to collide with a series of brilliant men at just the right time in my own development so that I could not only benefit from their teachings but also be turned into new directions which proved to be quite important. It is in this second category that I will speak tonight. The only way that I know to handle this is by a more or less personal, autobiographical approach, so perhaps my talk should really have been entitled, "My life with superconductors and superpeople." I got into superconductivity in the first place due to the teachings of two men, David Shoenberg, of whom many people here will know, and George Arthur Millward, who I am quite sure no one in this audience except my wife, Joan, will have ever heard of. I grew up in a small coastal town near the northern industrial belt of England during the great depression. My father was a modestly paid railroad worker. At least he had a regular job, which was not true for most of our relations. In the thirties our house was a regular stop-over place for destitute friends and relatives. I was very fortunate in two respects. First, my parents understood the value of education, which they, themselves, had been deprived of by economic circumstances. They were determined that I would not miss my opportunity. Second, I went to a first-rate high school headed by an exceptional educator, George Arthur Millward. G. A. Millward stood in fourteenth place on the mathematical first class honors list at Cambridge University in 1912, the year in which Sir Arthur Eddington, the future cosmologist, was first or senior wrangler. I'll spell that for those unfamiliar with the term - W-R-A-N-G-L-E-R. If you look up the word WRANGLER in the International edition of Webster's Dictionary you will find three definitions: FIRST: An angry or bickering disputant or argumentative person. SECOND: One who obtains first class honors in the mathematical tripos at Cambridge University. THIRD: A HORSE WRANGLER or COWBOY. The common thread in these definitions seems to be the word ARGUMENT. Apparently in ancient days the Cambridge mathematicians used to have a public argument with each other in order to determine the wranglers' pecking order. I don't know exactly how it worked, but it sounds like more fun than written examinations. Incidentally, the word TRIPOS comes from the Greek for a three-legged stool, which is what the early mathematicians are supposed to have sat upon while they conducted the wrangle. In the case of the cowboy, I suppose that his argument was with the horse, or was it with the cows? I don't know. So, George Arthur Millward was fourteenth wrangler in 1912. He was 6 foot 4 inches tall and in 1915 was heavy-weight boxing champion of the British Navy. Fortunately for me, he survived the battle of Jutland, and in 1919 he became the founding headmaster of our local high school. He was known as the BOSS, and kept discipline in the school with a large bamboo stick. For small boys, one stroke from that stick produced a NUMB POSTERIOR for the best part of a week, plus a firm resolve never again to incur the BOSS'S wrath. You might think that this man sounds like a BULLY. Well, he was certainly a strict disciplinarian, but he was much more complex than that. He went out of his way to stimulate any kind of schoolboy talent with special classes; he personally gave extra mathematics coaching to small groups of students year after year. At my last count, three fellows of the BRITISH ROYAL SOCIETY and three members of the U.S. National Academy of Engineering originated from that small high school in that small town, an achievement far out of proportion to the size of the local population. One of the graduates is currently president of the Bell Telephone Laboratories. I think a lot of credit is due to the fourteenth wrangler of 1912, George Arthur Millward. This little story is only relevant to the fact that I'm absolutely sure that if it hadn't been for that little-known but remarkable man, I wouldn't be standing here tonight. I suspect that the majority of scientists and engineers in this room can think of a teacher whose influence was crucial at some point in life. Well, Christmas is almost upon us, and it's a good time to recollect those who inspired you. If they are still alive, why don't you make a note to go see, phone, or send a card to say you were thinking of them and what a difference they made to your life? It would be a nice thing to do. Well, the BOSS got me into Cambridge University in 1941, and in my second year I met another remarkable man, David Shoenberg. He was teaching a class on electric and magnetic susceptibilities of materials based on VAN VLECK's famous textbook. The term solid-state physics was not then in general use, but David's course literally electrified me. I was absolutely intrigued by the thought that one could calculate the properties of a complex lump of matter from first principles. I think my future path was decided at that point. Graduate studies and basic research in physics at the Cavendish Laboratory had been suspended for the duration of the war, and Shoenberg was in fact working on proximity fuses when not teaching. He suggested that if we both survived the war, I might like to do graduate work with him, which I subsequently did. I'll spare you the details of my war memoirs. I worked on microwave radar equipment and electronic countermeasures for the Royal Air Force. It was very useful engineering experience, which I believe all physicists should have quite early in life. Well, with a little help from the United States and the Russians, we eventually won the war, and in 1946 I got out of the Air Force and became a graduate student at the Royal Society Mond Laboratory, a small low temperature research lab which was part of the Cavendish Physics Laboratory in Free School Lane, Cambridge. I'd like to explain how the Cavendish got into low temperature physics. As is well known, the Cavendish was the point of origin of much of modern physics, with the remarkable professorial sequence represented by James Clerk Maxwell, Lord Rayleigh, J. J. Thomson, who discovered the electron, and Ernest Rutherford, who founded nuclear physics. In the 1920s, Lord Rutherford's protégé was a Russian graduate student named Peter Kapitza, who was interested in the properties of matter at very high magnetic fields. In 1930, Kapitza managed to persuade Rutherford to get money from the MOND Nickel Company via the Royal Society to build a high magnetic field lab which became known as the MOND. This was a pulsed field lab, in which a large dc generator with a flywheel was discharged through a copper magnet. As his experiments proceeded, Kapitza thought it would be a good idea to cool the magnets down to low temperatures and he began to acquire cryogenic equipment. Being a very original thinker, he wanted to operate differently from the existing liquid helium research labs at Leiden and Berlin, which employed Joule-Thomson liquefiers using nitrogen, hydrogen, and helium in cascade. So, Kapitza constructed the first expansion engine to operate at liquid helium temperatures and thus avoided the hydrogen cycle. I subsequently used this primitive machine to get liquid helium for my thesis work. It was very temperamental, but it was the forerunner of the Collins liquefier, which triggered the great expansion of low temperature research in the U.S. in the 1950s. Now around 1935, Kapitza went back to the U.S.S.R., as he did every summer, for his annual vacation. Apparently it was suggested to him by the Soviet leaders that his services were needed in Moscow to build up Soviet science. He then started the famous Institute for Physical Problems, and he didn't return to Cambridge. The Mond continued to operate under the Canadian physicist, J. F. Alien, who had done pioneering work on superconducting alloys with McClennan at the University of Toronto, and David Shoenberg, who was one of Kapitza's graduate students. Now David Shoenberg was also of Russian origin. His parents had emigrated from Czarist Russia to England, where his father became director of research for Electrical and Musical Industries, a large electronics firm. In the late 1930s, David went over to visit Kapitza in Moscow. It was there that he wrote the first edition of his famous monograph on superconductivity, which has served to introduce many students to our subject. I'm sure that most of you know it. When I entered the Mond in 1946, I shared a small lab with another student, A. B. Pippard. Many of you will also remember Pippard's remarkable work on the anomalous skin effect in metals. This subsequently led to the concept of coherence length in superconductors and was one of the scientific paths which led to Abrikosov's theoretical discovery of type II superconductivity. Pippard also more or less invented FERMIOLOGY, and went on to become the Cavendish Professor himself. It was very frustrating to be blessed with a lab-mate like Pippard. With my own limited capacities, I seemed to find it necessary to work at least 12 to 15 hours a day in that lab to make even the slightest dent on my thesis problem. It always seemed to me that Pippard achieved astounding results with virtually no effort. He never showed up at all before lunch time. He would come in whistling cheerfully at about 2:30 p.m., turn a few valves, put in a little liquid helium, write down a few numbers, emit a few self-congratulatory grunts, and then announce that it was tea-time and disappear in the direction of the Cavendish tea-room. There he would hold forth on some abstract point of Greek mythology or some other esoteric subject which served to illustrate the broad range covered by his remarkable intellect. As far as I could tell, Pippard spent his evenings giving elegant dinners and playing Bach and Beethoven on a grand piano in his rooms. At one time I had a theory that he sneaked back into the lab late at night to do his experiments, but I was never able to catch him at it. Altogether, Pippard's image was rather terrifying to a working-class lad like myself. I don't want to give the impression that my life was all grind, either. Those immediate post-war summers were exceptionally warm and beautiful and I spent a lot of time on the River Cam with various girls, including eventually my wife, Joan, whom I met in 1948. I became expert in the art of punting. No, I wasn't trying to kick a ball for the local football team. I'm referring to the age-old English sport having to do with the propulsion of a flat-bottomed boat along the River Cam by means of a long pole. David Shoenberg's wife, Kate, discovered my talent for this activity and I was pressed into service to punt the wives and families of distinguished physicists who happened to be visiting the Mond. In this way I got to know the wives of Werner Heisenberg, Lars Onsager, Cornelius Gorter, Kurt Mendelssohn, and many others. I'm sure that my subsequent progress was partly due to this boat work. At this time there were only two sizable low temperature research labs in the United Kingdom, the Mond and our great archrival the Clarendon Lab in Oxford. The Clarendon low temperature facilities were also built up in the 1930s when Professor Lindemann took in a number of German refugees from the Hitler regime. This group was led by Francis Simon, who pioneered in another useful technique for liquefying helium by desorption from charcoal at high pressure. Simon was external examiner for my thesis and although I was scared stiff of him at first, this great low temperature pioneer proved to be kind and considerate. I had several pleasant interactions with him prior to his untimely death in the mid-1950s. Two other senior professors at the Clarendon were Nicholas Kurti, who pioneered in adiabatic cooling below 1 K, and Kurt Mendelssohn, who did a lot of original work on both liquid helium and superconductors for over 40 years and founded both our cryogenics journal and the International Cryogenic Engineering Conference. Mendelssohn came to Cambridge on one occasion to give a seminar and visited the various individual laboratories in the Mond, including mine. He seemed unusually interested in my experiments on heat conductivity in superconductors, and being rather wet behind the ears, I told him exactly what I was doing and described my experimental techniques in great detail. To this day I'm convinced that Mendelssohn immediately went back to Oxford and assigned a graduate student to do the identical experiments by the same method. They ran a crash program and ultimately beat me into print. Incidentally, that student was Jorgen Olsen, who subsequently became professor of physics at ETH in Zurich. He and I are good friends today. I hold Olsen completely innocent of unseemly behavior, he couldn't do it if he tried! He didn't learn of my work until my paper on thermal conductivity eventually came out. Well, at the time I was really annoyed. My boss, David Shoenberg, remonstrated gently with Mendelssohn, who merely, said that we didn't have a monopoly on heat conductivity at Cambridge and in any case he had worked on the topic before the war and therefore had prior claim. This experience taught me a lesson about the working of professorial minds, but I have to say that subsequently I got to know Kurt Mendelssohn very well indeed and received many kindnesses at his hands and from his family. In retrospect, I think that his behavior was simply governed by an unusual competitive drive which meant no harm to anyone, and I guess it didn't really hurt me in the long-run. In the post-war period we had a large number of foreign visitors to the Cavendish with a rich profusion of seminars in constant progress. These included U.S. luminaries such as J. C. Slater, Lars Onsager, and Linus Pauling. Sam Collins came over to tell us about his new helium liquefier, which was going into mass production at A. D. Little, but no one in our lab quite believed that there would be any market whatsoever for such machines. The staff shook their heads and said "what folly." We also had a lot of contact with the Kamerlingh-Onnes lab in Leiden. Professor Cornelius J. Gorter gave a lecture series at the Mond and he invited me for a visit to Leiden in 1948. Gorter's many contributions to physics included the two-fluid model of superconductors and the early concept of negative interphase energy as a cause of high field superconductivity. I would say that next to Shoenberg, he was my father figure in low temperature physics, and we had many interactions in later years — a wonderful man. Now when I first entered the Mond, I didn't immediately work on superconductors, because there was a shortage of liquid helium. Shoenberg suggested that I do some work on ferroelectric materials, in particular the properties of barium titanate. At the time this was known only in ceramic form, and we wanted to grow some single crystals to determine the exact dielectric properties. This problem also interested Sir Lawrence Bragg, then the head of the Cavendish. He assigned two crystallographers, Herbert Kay and Rene Rhodes, to work on this problem in a close collaboration with me. One of the pleasures of working on ferroelectricity was that I got to assist Sir Lawrence as demonstrator in a series of lectures which he gave on cooperative phenomena at the Royal Institution in London. I also got to demonstrate ferroelectricity in KDP at the Royal Society "conversazione," or evening discourses, which were attended by many distinguished people including the then Prime Minister, the Right Honorable Mr. Clement Attlee. Sir Lawrence Bragg was a great crystallographer. In his position as head of the Cavendish he followed four giant intellects, Maxwell, Rayleigh, Thomson, and Rutherford. Posterity will hopefully remember Bragg as the man who recognized the need for structural research on biological molecules and started the drive towards the spiral helix and modern bioengineering. But that's another story! We commenced our work on barium titanate late in 1946 and we messed around for about six months trying to grow single crystals from various molten fluxes. All we could get was black cruddy material with high conductivity. Then one day Professor Paul Scherrer from Zurich, of Debye-Scherrer fame, happened to be visiting Sir Lawrence at the Cavendish. When told of our difficulties, Scherrer remarked, "The correct flux for barium titanate is barium chloride." The next day we tried this recipe. Sure enough we soon obtained clear, insulating crystals of barium titanate. We measured their dielectric properties and Curie points and prepared a letter for publication in Nature. At the last minute, Sir Lawrence, a very ethical man, thought it best to check by telephone with Scherrer on the use of his recipe. The response was "No problem, go ahead and publish." Well, about two weeks after our paper appeared in print we got a rather nasty letter from one Bernd T. Matthias, also of Zurich, stating that we were unscrupulous pirates who had stolen his life's work, or words to that effect. This was followed shortly by an article by this person in Nature describing the properties of various perovskite dielectrics, such as barium titanate, but conspicuously omitting any reference to our earlier work. We wrote to Matthias explaining that Scherrer had given us clearance on publication, but he never replied to our letter. Well, I had almost forgotten about this incident in 1949, when I arrived at the University of Chicago to take a post-doctoral fellowship at the Institute for the Study of Metals. Joanie and I crossed the Atlantic on a ship from Liverpool to Halifax, Nova Scotia, and then by train across Canada and down to Chicago, all with a month-old baby. I already had the Ph.D. degree, but I needed to get the BTA, that is, "Been to America." Again, I didn't know it, but I was blundering into the highest concentration of physical intellect in North America, including not only Enrico Fermi and Edward Teller, but also many of the prime movers of the Manhattan project. It seems strange, nowadays, to recall the fact that there were relatively few low temperature research labs on the North American continent prior to World War II. As I recall, the prominent labs were at Toronto under McClennan, at Yale under C. T. Lane, at Berkeley under Giauque, and at the National Bureau of Standards under Brickwedde. After the war, two of Giauque's students, who had also worked in the Manhattan project, Earl Long and Willard Stout, constructed large (for that time) hydrogen and helium liquefiers of the Joule-Thomson type, in the old West Stand of Stagg field at the University of Chicago, right next door to the space where the first nuclear pile had been operated in 1942. One of the primary objectives was to provide concentrated proton targets for the new synchrocyclotron which Enrico Fermi and others were constructing on the other side of Ellis Avenue. Well, I went to work in the old west stand in November 1949. I soon met the chairman of the physics department, Andrew Lawson, who invited Joan and me to dinner at his house. Unbeknownst to me, this character Matthias from Zurich had just joined the department as assistant professor and was invited to the same dinner. When Mary Ann Lawson introduced me to Matthias, he said, "Hulm, Hulm, the Englishman? You can't be that blankety-blank Englishman who stole my work?" I said, "You mean barium chloride?" He said, "Come outside so I can kill you." Well, to cut a long story short, I managed to persuade him to postpone the murder until after we had eaten, by which time he was so pleased to find someone who had a background in ferroelectric materials that we began to plan some experiments together. This was another major turning point in my life. To explain, I need to tell a little bit of the history of Bernd Matthias: He was born in Frankfurt on Main, Germany, and was sent to Switzerland by his parents as a young man to escape the Nazis. He studied under Scherrer at Zurich and had worked at both MIT and Bell Labs before he came to Chicago. Prior to this time, he had already discovered a huge number of new ferroelectric materials, many of which have since proved to be of great importance for piezo-electric and electro-optical applications, for example, lithium niobate. His forte could be described as substitutional chemistry. He had a profound knowledge of the periodic table, atomic and ionic sizes, crystal structures, and an uncanny ability to predict new stable compositions. He also knew how to make new materials, especially single crystals. Matthias and I made a bargain. He would teach me materials chemistry if I would teach him low temperature physics. It was a good deal, for both of us. I never met a man who had a more copious flow of ideas for new materials than Bernd Matthias. He prepared new compounds and I liquefied helium all day, and we both measured them at night. If we got significant results, we celebrated with banana cream pie at Gordon's, an all-night dive on 57th Street. No results, no pie, that was the rule. In those days we had no effective storage vessels for liquid helium, at least not until the Wexler-type metal dewars became readily available in the middle fifties. Liquid helium had to be prepared just prior to each experiment. Our lab in the old west stand had been a squash court. It was incredibly dirty — I suspect we inherited a lot of graphite from the pile. In summer, with the external temperatures in the nineties, we were bathed in steam from a leaky steam line which was part of the campus heating system. This also provided hot water to the neighboring Argonne site and could not be shut off even in August. All this paled into insignificance because of the excitement of the work and the infectious enthusiasm which Bernd generated. Bernd had a Pontiac convertible and was always getting stopped for speeding. He drove as he worked — speedily. He taught me the Chicago trick of keeping a ten-dollar bill folded in with your license. The Chicago cops always asked for your license first, and of course, the bill was missing when you got it back, with a caution to be more careful. It's amazing that we didn't end up in the slammer. Bernd also taught me to drive, by a novel technique. He made me drive around backwards for several hours in the Soldier's field parking lot. It really works — it makes driving forward seem quite easy. We worked on ferroelectrics for about a year and found several new materials, particularly with Curie points at low temperature. From a theoretical viewpoint, these superdielectrics were reasonably well understood by 1950, whereas of course there was no satisfactory theory of superconductors. In casual conversation at lunchtime one day, Fermi remarked that superconductivity was a more important physical frontier — so why didn't we work on the materials aspects? Actually, Bernd and I had discussed this frequently, but Fermi's comment gave us the necessary impetus. Personally, I was doubtful about the usefulness of the chemical approach. The Cambridge, Oxford, and Leiden approach was definitely to concentrate on the physical aspects of more or less ideal superconductors such as tin, and of course, this paid off in the isotope effect discovery and led more or less directly to the BCS theory in 1957. The payoff for Matthias' chemical approach was quite different — it led eventually to high field superconductors and helped to foster the transition of superconductivity from a basic research phenomenon to a field with technological applications. Despite my misgivings, we directed our research at obtaining new materials with higher critical temperatures. Initially we examined carbides and nitrides of the transition metals, going over much of the ground already ploughed by Walter Meissner and his associates at the Physikalische Technische Reichsanstalt, in Berlin around 1930. We didn't get anything notable at first. In 1951 Matthias decided to quit the University of Chicago to return to Bell Labs. He had been on leave from the labs all along, and he was quite disappointed because he didn't obtain tenure at Chicago that year. We continued to exchange results and ideas by phone. In the spring of 1952 I was working with a graduate student, George Hardy. We decided that the carbides and nitrides were more or less exhausted, so we moved down to suicides and germanides in the second and third periods. We also began arc-melting our samples. These were two very fortunate moves. Not only was the general quality of the samples improved over our earlier sintered materials, but we soon discovered a new high Tc superconductor, V3Si, at 17 K. It belonged to what was then known, erroneously, as the beta-tungsten structure; of course this was subsequently changed to A15. I told this news to Bernd almost immediately. By then he had teamed up with Ted Geballe, Ernie Corenzwit, and Seymour Geller at the Bell Laboratories. These investigators proceeded to execute a tour-de-force in creative synthesis by discovering about 30 new A15's, including several new high Tc materials, most prominently Nb3Sn at 18 K, in 1954. At Chicago Matthias and I had also begun a preliminary study of the critical temperatures of the solid solution alloys of the transition metals, such as niobium-titanium and niobium-zirconium, but we had a lot of metallurgical difficulties with sintered samples. In 1954 I moved to the Westinghouse Research Laboratories in Pittsburgh. I was fortunate to meet Dick Blaugher shortly thereafter. Dick and I measured all of the nearest-neighbor body-centered cubic binary solid-solution alloys, just in time for the age of superconducting magnets, which was about to dawn, although we didn't know it at the time. It was well known to most superconductivity researchers at that time, in the fifties, that many superconducting alloys showed zero resistance at quite high fields, well above the normal or thermodynamic critical field. It was also a popular belief that this anomalous high field behavior was due to small regions of impurity or metallurgical defects. This carried with it the additional false assumption that these high field zones would normalize if subjected to appreciable electric currents. During the post-war decade, several experiments were done which should have destroyed some of these mistaken concepts regarding high field superconductivity, but the metallurgical defect model lingered on. For example, several investigators showed that cold-worked niobium wire was capable of carrying a current density exceeding 105 amperes per cm² at fields of several kilogauss — which greatly exceeded the thermodynamic critical field. At the University of Illinois in 1955, G. B. Yntema built a 7-kilogauss iron-cored magnet, using cold-worked niobium wire. S. Autler constructed similar magnets for maser applications in the late fifties. With a similar application in mind, a group led by J. E. Kunzler at the Bell Laboratories constructed a 15-kilogauss magnet using molybdenum-rhenium wire, in 1959. Slowly but surely, the possibility of high current densities and high fields became apparent. The situation was opened up with a bang in December 1960 when Kunzler's group found that the compound Nb3Sn would carry high electric current densities at fields approaching 10 Tesla. This breakthrough immediately started a major race in the United States through the summer of 1961 to construct high field superconducting magnets. The first thing that had to be done was to make a long length of superconducting wire — no small task at that time. The Bell Labs scientists employed a niobium-tin mixture in a niobium tube which was reacted after winding. There were two other groups seriously in the race. Ted Berlincourt and Dick Hake at Atomics International had made some elegant critical field measurements on the solid solution alloys. They teamed with the Wah Chang Company to obtain niobium-zirconium wire. At Westinghouse we also fixed on niobium-zirconium, which was made in our metallurgy department by Malcolm Frazer and R. A. Wien. Hank Riemersma and I built and tested the coils. The first phase of the big race came to somewhat of a climax at a conference on high magnetic fields which took place at MIT in the fall of 1961. The first three days of the meeting were devoted to ordinary high field magnets, but there was a special session on Saturday morning on the new magnets. The big auditorium was packed and there was an expectant hush — great results were anticipated. Gene Kunzler spoke first, and I was second. He said that the previous night they had run a magnet up to 68 kilogauss for the first time. They had beaten us again by a slight margin —we only had 60 kilogauss that week. When Gene had finished his paper, the projectionist in the booth accidentally mixed my slides together with Gene's and gave him the whole package. The result was that when I called for the first slide, they couldn't find it. It's not a good experience to go before a large, excited audience which is dying for information, only to be rendered more or less helpless. The chairman began to harangue the projectionist, who said he didn't have to take that from anybody and walked out. After 10 agonizing minutes, Gene Kunzler happened to look in his slide packet and discovered my missing slides. He promptly went to the booth and ran the projector for me. In the same session, Berlincourt, Hake, and Leslie reported field results almost identical with ours. Those tiny, primitive magnets were, of course, terribly unstable and tended to damage themselves on normalization, for reasons that are now well understood. One had to have faith to believe that these erratic toys of the low temperature physicist would ever be of any consequence as large engineered devices. Well, of course, the new technological prospects did create considerable excitement in the research community. I acquired a whole new circle of colleagues — some started out as competitors, but ended up as friends, as mostly happens in our field. Many of these men are here in this room tonight and they are the ones who made the technology grow; they helped to understand the anatomy of the flux jump and the instabilities of magnets and the techniques for protection of large coils. I regret that time does not allow me to go into the history of those first few exciting years of magnet development. There is enough material in that story for several after-dinner talks, which perhaps will be given at future conferences. At Westinghouse we had our ups and downs. In the mid-60's some of our highly paid executives decided that our work had no future and almost eliminated our superconductivity staff. Fortunately, enough of us survived in the woodwork to begin a rebuilding process, and today we have a large group which I can say is outstanding because I don't run it anymore. After the MIT meeting the Bell Laboratories decided not to proceed with magnet development, but they did continue the materials research program. In the late sixties Ted Geballe and Bernd Matthias scored another coup by achieving the first critical temperature above 20 Kelvin, with niobium-aluminum-germanium. I was especially pleased in 1972 when John Gavaler in our laboratory brought the record back to Pittsburgh, with niobium-3-germanium at 23 Kelvin, which is where things stand today. Bernd Matthias never took much part in magnet development, although he was certainly delighted with the rapid advance of the technology. He did continue to discover new superconductors and he turned out whole new families of ternary compounds which will keep the solid-state physics community busy in detailed investigations for many years to come. Matthias became a professor at the University of California, San Diego, and also worked actively with the materials group at Los Alamos. He continued his work at the Bell Laboratories. At times he would run a research program simultaneously at all three locations —this became known as "telephone physics." He was preparing to add a German laboratory to this Matthias Bell system at the time of his death in 1980. A month before Bernd died, we were together at the 1980 Applied Superconductivity Conference in Santa Fe. On the third day he said, as was his wont, "I've heard all this stuff before, let's get out of here." So we took some sandwiches and a bottle of wine and drove up to the mountains behind Los Alamos. As we sat on a high hill looking out over a magnificent New Mexico vista, Bernd said, "Hey, John, when we started out in the dirty old lab in the West Stand, did you ever think it would turn out like it did?" I replied, "No, Bernd, honestly, I DIDN'T think it would." 
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