Tag / Eugene Haller

by David D. Nolte

Anant K. Ramdas in the Golden Age of Physics

The physicist, as a gentleman and a scholar, who, in his leisure, pursues physics as both vocation and hobby, is an endangered species, though they once were endemic.  Classic examples come from the turn of the last century, as Rayleigh and de Broglie and Raman built their own laboratories to follow their own ideas.  These were giants in their fields. But there are also many quiet geniuses, enthralled with the life of ideas and the society of scientists, working into the late hours, following the paths that lead them forward through complex concepts and abstract mathematics as a labor of love.

One of these quiet geniuses, of late, was a colleague of mine and a friend, Anant K. Ramdas.  He was the last PhD student of the Nobel Prize Laureate, C. V. Raman, and he may have been the last of his kind as a gentleman and a scholar physicist.

Anant K. Ramdas

Anant Ramdas was born in May, 1930, in Pune, India, not far from the megalopolis of Mumbai when it had just over a million inhabitants (the number is over 22 million today, nearly a hundred years later).  His father, Lakshminarayanapuram A. Ramdas, was a scientist, a meteorologist who had studied under C. V. Raman at the University of Calcutta.  Raman won the Nobel Prize in Physics the same year that Anant Ramdas was born. 

Ramdas received his BS in Physics from the University of Pune in 1950, then followed in his father’s footsteps by studying for his MS (1953) and PhD (1956) degrees in Physics under Raman, who had established the Raman Institute in Bangalore, India. 

While facing the decision, after his graduation, on what to do and where to go, Ramdas read a review article published by Prof. H. Y. Fan of Purdue University on infrared spectroscopy of semiconductors.  After corresponding with Fan, and with the Purdue Physics department head, Prof. Karl Lark-Horowitz, Ramdas decided to accept the offer of a research associate (a post-doc position), and he prepared to leave India.

Within only a few months, he met and married his wife, Vasanti, and they hopped on a propeller plane to London that stopped along the way in Cairo, Beirut, Lebanon, and Paris before arriving in London.  From there, they caught a cargo ship making a two-week passage across the Atlantic, after stopping at ports in France and Portugal.  In New York City, they took a train to Chicago, getting off during a brief stop in the little corn-town of Lafayette, Indiana, home of Purdue University.  It was 1956, and Anant and Vasanti were, ironically, the first Indians that some people in the Indiana town had ever seen.

Semiconductor Physics at Purdue

Semiconductors became the ascendent electronic material during the Second World War when it was discovered that their electrical properties were ideal for military radar applications.  Many of the top physicists of the time worked at the “Rad Lab”, the Radiation Laboratory of MIT, and collaborations spread out across the US, including to the Physics Department at Purdue University.  Researchers at Purdue were especially good at growing the semiconductor Germanium, which was used in radar rectifiers.  The research was overseen by Lark-Horowitz.

After the war, semiconductor research continued to be a top priority in the Purdue Physics department as groups around the world competed to find ways to use semiconductors instead of vacuum tubes for information and control.  Friendly competition often meant the exchange of materials and samples, and sometime in early 1947, several Germanium samples were shipped to the group of Bardeen and Brattain at Bell Labs, where, several months later, they succeeded in making the first point contact transistor using Germanium (with some speculation today that it may have been with the samples sent from Purdue).  It was a close thing. Ralph Bray, a professor at Purdue, had seen nonlinear current dependences in the Purdue-grown Germanium samples that were precursers of transistor action, but Bell made the announcement before Bray had a chance to take the next step. Lark-Horowitz (and Bray) never forgot how close Purdue had come to making the invention themselves [1].

Bray_1997_Electrochem._Soc._Interface_6_24Download

In 1948, Lark-Horowitz hired H. Y. Fan, who had received his PhD at MIT in 1937 and had been teaching at Tsinghua University in China.  Fan was an experimental physicist specializing in the infrared properties of semiconductors, and when Ramdas arrived at Purdue in 1956, he worked directly under Fan.  They published their definitive work on the infrared absorption of irradiated silicon in 1959 [2].

Absorption spectrum of “effective-mass” shallow defect levels in irradiated silicon.

FanRamdasDownload

One day, while Ramdas was working in Fan’s lab, Lark-Horowitz stopped by, as he was accustomed to do, and he casually asked if Ramdas would be interested in becoming a professor at Purdue.  Ramdas of course said “Yes”, and Lark-Horowitz gave him the job on the spot.  Ramdas was appointed as an assistant professor in 1960.  These things were less formal in those days, and it was only later that Ramdas learned that Fan had already made a strong case for him.

The Golden Age of Physics

The period from 1960 to 2015, which spanned Ramdas’ career, start to finish, might be called “The Golden Age of Physics”. 

This time span saw the completion of the Standard Model of particle physics with the theory of quarks (1964), the muon neutrino (1962), electro-weak unification (1968), quantum chromodynamics (1970s), the tau lepton (1975), the bottom quark (1977), the top quark (1995), the W and Z bosons (1983), the tau neutrino (2000), neutrino mass oscillations (2004), and of course capping it off with the detection of the Higgs boson (2012). 

This was the period in solid state physics that saw the invention of the laser (1960), the quantum Hall effect (1980), the fractional quantum Hall effect (1982), scanning tunneling microscopy (1981), quasi-crystals (1982), high-temperature superconductors (1986), and graphene (2005).

This was also the period when astrophysics witnessed the discovery of the Cosmic Background Radiation (1964), the first black hole (1964), pulsars (1967), confirmation of dark matter (1970s), inflationary cosmology (1980s), Baryon Acoustic Oscillations (2005), and capping the era off with the detection of gravitational waves (2015).

The period from 1960 – 2015 stands out relative to the “first” Golden Age of Physics from 1900 – 1930 because this later phase is when the grand programs from early in the century were brought largely to completion.

But these are the macro-events of physics from 1960-2015.  This era was also a Golden Age in the micro-events of the everyday lives of the physicists.  It is this personal aspect where this later era surpassed the earlier era (when only a handful of physicists were making progress).  In the later part of the century, small armies of physicists were advancing rapidly along all the frontiers at the same time, and doing it with the greatest focus.

This was when a single NSF grant could support a single physicist with several grad students and an undergraduate or two.  The grants could be renewed with near certainty, as long as progress was made and papers were published.  Renewal applications, in those days, were three pages.  Contrast that to today when 25 pages need to be honed to perfection—and then the renewal rate is only about 10% (soon to be even lower with the recent budget cuts to science in the USA).  In those earlier days, the certainty of success, and the absence of the burden of writing multiple long grant proposals, bred confidence to dispose of the conventional, to try anything new.  In other words, the vast amount of time spent by physicists during this Golden Age was in the pursuit of physics, in the classroom and in the laboratory.

And this was the time when Anant Ramdas and his cohort—Sergio Rodriguez, Peter Fisher, Jacek Furdyna, Eugene Haller, the Chandrasekhar’s, Manuel Cardona, and the Dresselhaus’s—rode the wave of semiconductor physics when money was easy, good students were plentiful, and a vibrant intellectual community rallied around important problems.

Selected Topics of Research from Anant Ramdas

It is impossible to give justice to the breadth and depth of research performed by Anant over his career. So here is my selection of some of my favorite examples of his work:

Diamond

Anant had a life-long fascination for diamonds. As a rock and gem collector, he was fond of telling stories about the famous Cullinan diamond (weighed 1.3 pounds as a raw diamond at 3000 carats) and the blue Hope diamond (discovered in India). One of his earliest and most cited papers was on the Raman spectrum of Diamond [3], and he published several papers on his favorite color for diamonds—Blue [4]!

Raman Spectrum of Diamond.

DiamondPhysRevB.1.1687Download

His work on diamond helped endear Anant with the husband-wife team of Milly Dresselhaus and Gene Dresselhaus at MIT. Milly was the “Queen” of carbon, known for her work on graphite, carbon nanotubes and Fullerenes. Purdue had made an offer of an assistant professorship to Gene Dresselhaus when the two were looking for faculty positions after their post-docs at the University of Chicago, but Purdue would not give Milly a position (she was viewed as a “trailing” spouse). Anant was already at Purdue at that time and got to know both of them, maintaining a life-long friendship. Milly went on to become the president of the APS and was elected a member of the National Academy of Sciences, the National Academy of Engineering and the American Academy of Arts and Sciences.

Magneto-Optics

Purdue was a hot-bed of II-VI semiconductor research in the 1980’s, spearheaded by Jacek Furdyna. The substitution of the magnetic ion Mn for Zn, Cd or Hg created a unique class of highly magnetic semiconductors. Anant was the resident expert on the optical properties of the materials and collected one of the best examples of Giant Faraday Rotation [5].

Giant Faraday Effect in CdMnTe

FaradayPhysRevBDownload

Anant and the Purdue team were the world leaders in the physics and materials science of diluted magnetic semiconductors.

Shallow Defects in Semiconductors

My own introduction to Anant was through his work on shallow effective-mass defect states in semiconductors. I was working towards my PhD with Eugene ‘Gene” Haller at Lawrence Berkeley Lab (LBL) in the early 1980’s, and Gene was an expert on the spectroscopy of the shallow levels in Germanium. My co-physics graduate student colleague was Joe Kahn, and the two of us were tasked with studying the review article that Anant had written with his long-time theoretical collaborator Sergio Rodriguez on the physics of effective-mass shallow defects in semiconductors [6]. We called it “The Bible”, and spent months studying it. Gene Haller’s principal technique was photothermal ionization spectroscopy (PTIS), and Joe was building the world’s finest PTIS instrument. Joe met Anant for dinner one night at the March meeting of the APS in 1986, and when he got back to the room, he waxed poetic about Anant for an hour. It was like he had met his hero. I don’t remember how I missed that dinner, so my personal introduction to Anant Ramdas would have to wait.

PTIS spectra of donors in GaAs

Ramdas_1981_Rep._Prog._PhysDownload

My own research went into deep-level transient spectroscopy (DLTS) working with Gene and his group theorist, Wladek Walukiewicz, where we discovered a universal pressure derivative in III-V semiconductors. This research led me to a post-doc position at Bell Labs under Alastair Glass and later to a faculty position at Purdue, where I did finally meet Anant, who became my long-time champion and mentor. But Joe had stayed with the shallow defects, and in particular defects that showed interesting dynamical properties, known as tunneling defects.

Dynamic Defects in Semiconductors

Dynamic defects in semiconductors are multicomponent defects (often involving vacancies or interstitial defects) in which one of the components tunnels quantum mechanically, or hops, rapidly on a time scale short compared to the measurement interaction time (electric dipole transition), so that the measurement sees increased symmetry compared to the instantaneous low-symmetry configuration of the defect.

Eugene Haller and his physics theory collaborator, Leo Falicov, were pioneers in tunneling defects related to hydrogen, building on earlier work by George Watkins who studied dynamical defects using EPR measurements. In my early days doing research under Eugene, we thought we had discovered a dynamical effect in FeB defects in silicon, and I spent two very interesting weeks at Lehigh University, visiting Watkins, to test out our idea, but it turned out to be a static effect. Later, Joe Kahn found that some of the early hydrogen defects in Germanium that Gene and Leo had proposed as dynamical defects were also, in fact, static. So the class of dynamical defects in semiconductors was actually shrinking over time rather than expanding. Joe did go on to find clear proof of a hydrogen-related dynamical defect in Germanium, saving the Haller-Falicov theory from the dust bin of Physics History.

In 2006 and in 2008, Ramdas was working on Oxygen-related defect complexes in CdSe when his student, G. Chen [7-8], discovered a temperature-induced symmetry raising. It showed clear evidence for a lower symmetry defect that converged into a higher symmetry mode at high temperatures, very much in agreement with the Haller-Falicov theory of dynamical symmetry raising.

At that time, I was developing my course notes for my textbook Introduction to Modern Dynamics, where some of the textbook problems in synchronization looked just like Anant’s data. Using a temperature-dependent coupling in a model of nonlinear (anharmonic) oscillators, I obtained the following fits (solid curves) to the Ramdas data (data points):

Quantum synchronization in CdSe and CdTe.

DoubletPhysRevLettDownload
TripletPhysRevLettDownload

The fit looks too good to be a coincidence, and Anant and I debated on whether the Haller-Falicov theory, or a theory based on nonlinear synchronization, would be better descriptions of the obviously dynamical properties of these defects. Alas, Anant is now gone, and so are Gene and Leo, so I am the last one left thinking about these things.

Beyond the Golden Age?

Anant Ramdas was fortunate to have spent his career during the Golden Age of Physics, when the focus was on the science and on the physics, as healthy communities helped support one another in friendly competition. He was a gentleman scholar, an avid reader of books on history and philosophy, much of it (but not all) on the history and philosophy of physics. His “Coffee Club” at 9:30 AM every day in the Physics Department at Purdue was a must-not-miss event that was attended by all of the Old Guard as well as by myself, where the topics of conversation ran the gamut, presided over by Anant. He had his NSF grant, year after year (and a few others), and that was all he needed to delve into the mysteries of the physics of semiconductors.

Is that age over? Was Anant one of the last of that era? I can only imagine what he would say about the current war against science and against rationality raging across the USA right now, and the impending budget cuts to all the science institutes. He spent his career and life upholding the torch of enlightenment. Today, I fear he would be holding it in the dark. He passed away Thanksgiving, 2024.

Vasanti and Anant, 2022.

References

[1] Ralph Bray, “A Case Study in Serendipity”, The Electrochemical Society, Interface, Spring 1997.

[2] H. Y. Fan and A. K. Ramdas, “INFRARED ABSORPTION AND PHOTOCONDUCTIVITY IN IRRADIATED SILICON,” Journal of Applied Physics, Article vol. 30, no. 8, pp. 1127-1134, 1959, doi: 10.1063/1.1735282.

[3] S. A. Solin and A. K. Ramdas, “RAMAN SPECTRUM OF DIAMOND,” Physical Review B, Article vol. 1, no. 4, pp. 1687-&, 1970, doi: 10.1103/PhysRevB.1.1687

[4] H. J. Kim, Z. Barticevic, A. K. Ramdas, S. Rodriguez, M. Grimsditch, and T. R. Anthony, “Zeeman effect of electronic Raman lines of accepters in elemental semiconductors: Boron in blue diamond,” Physical Review B, Article vol. 62, no. 12, pp. 8038-8052, Sep 2000, doi: 10.1103/PhysRevB.62.8038.

[5] D. U. Bartholomew, J. K. Furdyna, and A. K. Ramdas, “INTERBAND FARADAY-ROTATION IN DILUTED MAGNETIC SEMICONDUCTORS – ZN1-XMNXTE AND CD1-XMNXTE,” Physical Review B, Article vol. 34, no. 10, pp. 6943-6950, Nov 1986, doi: 10.1103/PhysRevB.34.6943.

[6] A. K. Ramdas and S. Rodriguez, “SPECTROSCOPY OF THE SOLID-STATE ANALOGS OF THE HYDROGEN-ATOM – DONORS AND ACCEPTORS IN SEMICONDUCTORS,” Reports on Progress in Physics, Review vol. 44, no. 12, pp. 1297-1387, 1981, doi: 10.1088/0034-4885/44/12/002

[7] G. Chen, I. Miotkowski, S. Rodriguez, and A. K. Ramdas, “Stoichiometry driven impurity configurations in compound semiconductors,” Physical Review Letters, Article vol. 96, no. 3, Jan 2006, Art no. 035508, doi: 10.1103/PhysRevLett.96.035508.

[8] G. Chen, J. S. Bhosale, I. Miotkowski, and A. K. Ramdas, “Spectroscopic Signatures of Novel Oxygen-Defect Complexes in Stoichiometrically Controlled CdSe,” Physical Review Letters, Article vol. 101, no. 19, Nov 2008, Art no. 195502, doi: 10.1103/PhysRevLett.101.195502.

Other Notable Papers:

[9] E. S. Oh, R. G. Alonso, I. Miotkowski, and A. K. Ramdas, “RAMAN-SCATTERING FROM VIBRATIONAL AND ELECTRONIC EXCITATIONS IN A II-VI QUATERNARY COMPOUND – CD1-X-YZNXMNYTE,” Physical Review B, Article vol. 45, no. 19, pp. 10934-10941, May 1992, doi: 10.1103/PhysRevB.45.10934.

[10] R. Vogelgesang, A. K. Ramdas, S. Rodriguez, M. Grimsditch, and T. R. Anthony, “Brillouin and Raman scattering in natural and isotopically controlled diamond,” Physical Review B, Article vol. 54, no. 6, pp. 3989-3999, Aug 1996, doi: 10.1103/PhysRevB.54.3989.

[11] M. H. Grimsditch and A. K. Ramdas, “BRILLOUIN-SCATTERING IN DIAMOND,” Physical Review B, Article vol. 11, no. 8, pp. 3139-3148, 1975, doi: 10.1103/PhysRevB.11.3139.

[12] E. S. Zouboulis, M. Grimsditch, A. K. Ramdas, and S. Rodriguez, “Temperature dependence of the elastic moduli of diamond: A Brillouin-scattering study,” Physical Review B, Article vol. 57, no. 5, pp. 2889-2896, Feb 1998, doi: 10.1103/PhysRevB.57.2889.

[13] A. K. Ramdas, S. Rodriguez, M. Grimsditch, T. R. Anthony, and W. F. Banholzer, “EFFECT OF ISOTOPIC CONSTITUTION OF DIAMOND ON ITS ELASTIC-CONSTANTS – C-13 DIAMOND, THE HARDEST KNOWN MATERIAL,” Physical Review Letters, Article vol. 71, no. 1, pp. 189-192, Jul 1993, doi: 10.1103/PhysRevLett.71.189.

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by David D. Nolte

Physics and the Zen of Motorcycle Maintenance

When I arrived at Berkeley in 1981 to start graduate school in physics, the single action I took that secured my future as a physicist, more than spending scores of sleepless nights studying quantum mechanics by Schiff or electromagnetism by Jackson —was buying a motorcycle!  Why motorcycle maintenance should be the Tao of Physics was beyond me at the time—but Zen is transcendent.

1978_GS550_blk_leftside_520

The Quantum Sadistics

In my first semester of grad school I made two close friends, Keith Swenson and Kent Owen, as we stayed up all night working on impossible problem sets and hand-grading a thousand midterms for an introductory physics class that we were TAs for.  The camaraderie was made tighter when Keith and Kent bought motorcycles and I quickly followed suit, buying my first wheels –– a 1972 Suzuki GT550.    It was an old bike, but in good shape and ready to ride, so the three of us began touring around the San Francisco Bay Area together on weekend rides.  We went out to Mt. Tam, or up to Vallejo, or around the North and South Bay.  Kent thought this was a very cool way for physics grads to spend their time and he came up with a name for our gang –– the “Quantum Sadistics”!  He even made a logo for our “colors” that was an eye shedding a tear drop shaped like the dagger of a quantum raising operator.

At the end of the first year, Keith left the program, not sure he was the right material for a physics degree, and moved to San Diego to head up the software arm of a start-up company that he had founder’s shares in.  Kent and I continued at Berkeley, but soon got too busy to keep up the weekend rides.  My Suzuki was my only set of wheels, so I tooled around with it, keeping it running when it really didn’t want to go any further.  I had to pull its head and dive deep into it to adjust the rockers.  It stayed together enough for a trip all the way down Highway 1 to San Diego to visit Keith and back, and a trip all the way up Highway 1 to Seattle to visit my grandparents and back, having ridden the full length of the Pacific Coast from Tijuana to Vancouver.  Motorcycle maintenance was always part of the process.

Andrew Lange

After a few semesters as a TA for the large lecture courses in physics, it was time to try something real and I noticed a job opening posted on a bulletin board.  It was for a temporary research position in Prof. Paul Richard’s group.  I had TA-ed for him once, but knew nothing of his research, and the interview wasn’t even with him, but with a graduate student named Andrew Lange.  I met with Andrew in a ground-floor lab on the south side of Birge Hall.  He was soft-spoken and congenial, with round architect glasses, fine sandy hair and had about him a hint of something exotic.  He was encouraging in his reactions to my answers.  Then he asked if I had a motorcycle.  I wasn’t sure if he already knew, or whether it was a test of some kind, so I said that I did.  “Do you work on it?”, he asked.  I remember my response.  “Not really,” I said.  In my mind I was no mechanic.  Adjusting the overhead rockers was nothing too difficult.  It wasn’t like I had pulled the pistons.

“It’s important to work on your motorcycle.”

For some reason, he didn’t seem to like my answer.  He probed further.  “Do you change the tires or the oil?”.  I admitted that I did, and on further questioning, he slowly dragged out my story of pulling the head and adjusting the cams.  He seemed to relax, like he had gotten to the bottom of something.  He then gave me some advice, focusing on me with a strange intensity and stressing very carefully, “It’s important to work on your motorcycle.”

I got the job and joined Paul Richards research group.  It was a heady time.  Andrew was designing a rocket-borne far-infrared spectrometer that would launch on a sounding rocket from Nagoya, Japan.  The spectrometer was to make the most detailed measurements ever of the cosmic microwave background (CMB) radiation during a five-minute free fall at the edge of space, before plunging into the Pacific Ocean.  But the spectrometer was missing a set of key optical elements known as far-infrared dichroic beam splitters.  Without these beam splitters, the spectrometer was just a small chunk of machined aluminum.  It became my job to create these beam splitters.  The problem was that no one knew how to do it.  So with Andrew’s help, I scanned the literature, and we settled on a design related to results from the Ulrich group in Germany.

Our spectral range was different than previous cases, so I created a new methodology using small mylar sheets, patterned with photolithography, evaporating thin films of aluminum on both sides of the mylar.  My first photomasks were made using an amazingly archaic technology known as rubylith that had been used in the 70’s to fabricate low-level integrated circuits.  Andrew showed me how to cut the fine strips of red plastic tape at a large scale that was then photo-reduced for contract printing.  I modeled the beam splitters with equivalent circuits to predict the bandpass spectra, and learned about Kramers-Kronig transforms to explain an additional phase shift that appeared in the interferometric tests of the devices.  These were among the first metamaterials ever created (although this was before that word existed), with an engineered magnetic response for millimeter waves.  I fabricated the devices in the silicon fab on the top floor of the electrical engineering building on the Berkeley campus.  It was one of the first university-based VLSI fabs in the country, with high-class clean rooms and us in bunny suits.  But I was doing everything but silicon, modifying all their carefully controlled processes in the photolithography bay.  I made and characterized a full set of 5 of these high-tech beam splitters–right before I was ejected from the lab and banned.  My processes were incompatible with the VLSI activities of the rest of the students.  Fortunately, I had completed the devices, with a little extra material to spare.

I rode my motorcycle with Andrew and his friends around the Bay Area and up to Napa and the wine country.  One memorable weekend Paul had all his grad students come up to his property in Mendocino County to log trees.  Of course, we rode up on our bikes.  Paul’s land was high on a coastal mountain next to the small winery owned by Charles Kittel (the famous Kittel of “Solid State Physics”).  The weekend was rustic.  The long-abandoned hippie-shack on the property was uninhabitable so we roughed it.  After two days of hauling and stacking logs, I took a long way home riding along dark roads under tall redwoods.

Andrew moved his operation to the University of Nagoya, Japan, six months before the launch date.  The spectrometer checked out perfectly.  As launch day approached, it was mounted into the nose cone of the sounding rocket, continuing to pass all calibration tests.  On the day of launch, we held our breath back in Berkeley.  There was a 12 hour time difference, then we received the report.  The launch was textbook perfect, but at the critical moment when the explosive nose-cone bolts were supposed to blow, they failed.  The cone stayed firmly in place, and the spectrometer telemetered back perfect measurements of the inside of the rocket all the way down until it crashed into the Pacific, and the last 9 months of my life sank into the depths of the Marianas Trench.  I read the writing on the thin aluminum wall, and the following week I was interviewing for a new job up at Lawrence Berkeley Laboratory, the DOE national lab high on the hill overlooking the Berkeley campus.

Eugene Haller

The  instrument I used in Paul Richard’s lab to characterize my state-of-the-art dichroic beamsplitters was a far-infrared Fourier-transform spectrometer that Paul had built using a section of 1-foot-diameter glass sewer pipe.  Bob McMurray, a graduate student working with Prof. Eugene Haller on the hill, was a routine user of this makeshift spectrometer, and I had been looking over Bob’s shoulder at the interesting data he was taking on shallow defect centers in semiconductors.   The work sounded fascinating, and as Andrew’s Japanese sounding rocket settled deeper into the ocean floor, I arranged to meet with Eugene Haller in his office at LBL.

I was always clueless about interviews.  I never thought about them ahead of time, and never knew what I needed to say.  On the other hand, I always had a clear idea of what I wanted to accomplish.  I think this gave me a certain solid confidence that may have come through.  So I had no idea what Eugene was getting at as we began the discussion.  He asked me some questions about my project with Paul, which I am sure I answered with lots of details about Kramers-Kronig and the like.  Then came the question strangely reminiscent of when I first met Andrew Lange:  Did I work on my car?  Actually, I didn’t have a car, I had a motorcycle, and said so.  Well then, did I work on my motorcycle?  He had that same strange intensity that Andrew had when he asked me roughly the same question.  He looked like a prosecuting attorney waiting for the suspect to incriminate himself.  Once again, I described pulling the head and adjusting the rockers and cams.

Eugene leaned back in his chair and relaxed.  He began talking in the future tense about the project I would be working on.  It was a new project for the new Center for Advanced Materials at LBL, for which he was the new director.  The science revolved around semiconductors and especially a promising new material known as GaAs.  He never actually said I had the job … all of a sudden it just seemed to be assumed.  When the interview was over, he simply asked me to give him an answer in a few days if I would come up and join his group.

I didn’t know it at the time, by Eugene had a beautiful vintage Talbot roadster that was his baby.  One of his loves was working on his car.  He was a real motor head and knew everything about the mechanics.  He was also an avid short-wave radio enthusiast and knew as much about vacuum tubes as he did about transistors.  Working on cars (or motorcycles) was a guaranteed ticket into his group.  At a recent gathering of his former students and colleagues for his memorial, similar stories circulated about that question:  Did you work on your car?  The answer to this one question mattered more than any answer you gave about physics.

I joined Eugene Haller’s research group at LBL in March of 1984 and received my PhD on topics of semiconductor physics in 1988.  My association with his group opened the door to a post-doc position at AT&T Bell Labs and then to a faculty position at Purdue University where I currently work on the physics of oncology in medicine and have launched two biotech companies—all triggered by the simple purchase of a motorcycle.

Boomerang

BOOMERanG in Antarctica (1997)

Andrew Lange’s career was particularly stellar.  He joined the faculty of Cal Tech, and I was amazed to read in Science magazine in 2004 or 2005, in a section called “Nobel Watch”, that he was a candidate for the Nobel Prize for his work on BoomerAng that had launched and monitored a high-altitude balloon as it circled the South Pole taking unprecedented data on the CMB that constrained the amount of dark matter in the universe.  Around that same time I invited Paul Richards to Purdue to give our weekly physics colloquium to talk about his own work on MAXIMA. There was definitely a buzz going around that the BoomerAng and MAXIMA collaborations were being talked about in Nobel circles. The next year, the Nobel Prize of 2006 was indeed awarded for work on the Cosmic Microwave Background, but to Mather and Smoot for their earlier work on the COBE satellite.

Then, in January 2010, I was shocked to read in the New York Times that Andrew, that vibrant sharp-eyed brilliant physicist, was found lifeless in a hotel room, dead from asphyxiation.  The police ruled it a suicide.  Apparently few had known of his life-long struggle with depression, and it had finally overwhelmed him.  Perhaps he had sold his motorcycle by then.  But I wonder—if he had pulled out his wrenches and gotten to work on its engine, whether he might have been enveloped by the zen of motorcycle maintenance and the crisis would have passed him by.  As Andrew had told me so many years ago, and I wish I could have reminded him, “It’s important to work on your motorcycle.”