Friday, September 06, 2019

Big questions about condensed matter (part 3)

More questions asked by Ross McKenzie's son about the culture/history of condensed matter physics:

3.  What are the most interesting historical anecdotes?  What are the most significant historical events?  Who were the major players?

The first couple of these are hard to address in anything resembling an unbiased way.  For events that happened before I was in the field, I have to rely on stories I've read or things I've heard.  Certainly the discovery of superconductivity by Onnes is a good example - where they thought that they had an experimental problem with their wiring, until they realized that their voltmeter reading dropping to zero (trying to measure the voltage drop across some mercury in the presence of a known current) happened at basically the same temperature every time.  (Pretty good for 1911!).  Major experimental results very often have fun story components.  From my thesis adviser, I'd heard lots of stories about the discovery of superfluidity in 3He, including plugging a leaky vacuum flange using borax; thinking up the experiment while recovering from a broken leg skiing accident; the wee-hour phone call to the adviser.   He also told me a story about this paper, where he and Gerry Dolan came up with a very clever way to see tiny deviations away from a mostly linear current-voltage curve, an observation connected with weak localization that paved the way for a lot of mesoscopic physics work.   

There are fun theory stories, too.  Bob Laughlin figuring out the theory of the fractional quantum Hall effect while stuck in a trailer at Livermore because his clearance paperwork hadn't come through yet.

Other stories I've read in books.  Strong recommendations for Crystal Fire; the less popular/more scholarly Out of the Crystal MazeOhl's discovery of the photovoltaic effect in silicon.  The story about how Bell Labs and IBM researchers may or may not have traded hints poolside in Las Vegas about how to get field-effect transistors really working.  Shockley's inability to manage people eventually resulting in Silicon Valley.  

These aren't necessarily the best anecdotes, but they have elements of interest.  I'm sure there are many out there who could tell fun stories.

As for the major players, it seems that everyone mentioned on Prof. McKenzie's post and in the comments are theorists.  That seems limiting.  It's fair to talk about theorists if you're concentrating on theoretical developments, but experimentalists have often opened up whole areas.  Onnes liquefied helium and discovered superconductivity.  Laue invented x-ray diffraction.  Brattain made transistors.  Nick Holonyak was an inventor of the light emitting diode, which has been revolutionary.   Binnig and Rohrer invented the STM.  Bednorz and Muller discovered the cuprates.  


4 comments:

Anonymous said...

I think it was Fairchild and Bell Labs engineers who traded notes on MOSFET technology as opposed to IBM and Bell Labs engineers.

Anonymous said...

Nice post! On the note of crediting experimental physicists, here's a quick question:

For particle physicists in the old days, Luis Alvarez was the clever experimentalist everybody wanted to be. Who is the "Luis Alvarez" of condensed matter in the old days? And in modern times?

Douglas Natelson said...

Anon@8:02, I think you’re right. I was working from memory, rather than digging out my copy of Crystal Fire.

Anon@11:29, great question. Back in the day, I’m not sure - perhaps others will have good suggestions. My perspective is strongly affected by people I’ve encountered. Paul McEuen is very impressive as well as having broad interests. Phuan Ong has done work with an impressive variety of materials systems and techniques. Don Eigler and his intellectual progeny have done great things for STM, as has Seamus Davis. David Awschalom and John Martinis have always struck me as completely fearless about trying new, difficult things. I’m hesitant to start listing people, since I don’t want to stir up anyone by accidental omission.

Alberto said...

You mention several times that the discovery of high-Tc superconductivity in cuprates was "a surprise". As a matter of fact, it was so for everyone except ... Bednorz and Mûller, who had been looking for years into these perovskite-type oxides ceramics as potential high-Tc superconductors. Their reasoning--which nowadays everyone believes was wrong--was that strong electron-phonon interactions in oxides can occur because of polaron formation. The mechanism they had in mind, and that they systematically searched for in these materials, was polaron formation by the Jahn-Teller effect. Isolated Fe4+ and Cu2+ ions in an octahedral oxygen environment were known to exhibit strong Jahn-Teller effects; oxygen deficiency in Cu based materials produced mixed valence phases, in which Cu3+ ions (that do not exhibit J-T effect) coexisted with Cu2+ ions and were expected to exhibit itinerant electronic states with strong electron-phonon coupling. They were so sure they had found high-Tc superconductivity when they observed the resistivity drop to zero, that they published their results before testing for the Meissner effect (albeit with a cautious title: "Possible high-Tc superconductivity ...". It would seem that the discovery of high-Tc superconductivity is a good example of "right for the wrong reasons"!