Sunday, April 13, 2008

Talk this week

First, to the readers of this blog, thanks for the recent trend of posting informative links in the comments. I think that this really adds something to the discussion. One tip: in the comments you're allowed to use html tags, so if you want to post a link with a long URL, you may want to write the html that actually posts the link.

This week we had a fun physics colloquium given by Paul Canfield of Ames Lab and Iowa State University. He spoke about the discovery and characterization of new materials, with a particular emphasis on heavy fermion compounds, but with a significant discussion of MgB2 as well. His main purpose was to convey how physicists like him think and approach problems, and I think he succeeded. He also had a funny slide called "Periodic Table According to Most Physicists" that looked roughly like this:

H                                       H' (almost like hydrogen)
H'' H'''                  C       H'''' H'''''
                        Si
        Metals       Cu

                     Au

   Elements that may not even be real


         |<---Not on the final exam --->|
         |<---Stuff for bombs  -------->|

Amusing stuff.
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7 comments:

  1. Schlupp12:34 PM

    Except that one could perhaps name one or two more metals explicitly and that some of the stuff that's not gonna be on the exam might be interesting, where 's the problem with that table?

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  2. jonah1:34 AM

    Where's bismuth? That was one of the most important (semi)metals in the development of solid state physics and in particular for discoveries of quantum effects in macroscopic materials. Many first discoveries of quantum oscillations in magnetic, thermodynamic, etc. quantities were discovered there by the giants of the early solid state (de Haas-van Alphen, Shubnikov-de Haas, first experimental Fermi surface by Shoenberg, discovery of the Nernst effect by Nernst and Ettinghausen). And even recently potential signatures of the fractional quantum hall state were seen in bismuth (Science 317,1729(2007)).

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  3. CarlBrannen2:12 AM

    Better than astrophysicists who think that everything other than hydrogen and helium is "metalicity".

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  4. Anonymous11:52 AM

    Are "rare earth" elements really rare ? They seem to be everywhere ...

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  5. Schlupp7:05 PM

    okham, as far as I know they are not particularly rare. (Well yes they are compared to H in the universe.) But apparently they were considered highly exotic when they were discovered. Since they all have very similar chemistry, they were hard to separate and that made them hard to discover. I mean, if you go through all that hassle to find an element, it'd better be something really special!

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  6. Anonymous8:17 PM

    Amusing, except of course that Helium was left out. In fact, 3He and 4He should really be considered different elements, in this sort of approximation.

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  7. Anonymous1:44 PM

    I'm willing to put in my vote for bismuth. I was unaware of its historical importance, but it is one of the most fun elements to say aloud. Try it. Go ahead. Almost as much fun as "dysprosium".

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