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Pauli Exclusion in Metals

  1. Sep 30, 2006 #1
    Hello,
    I was wondering if the Pauli Exclusion principle still applies to electrons in a metal. My intitution tells me no since a magnetic field acting on a metal causes the electron spin to realign but I am not sure.

    Thanks,
    -scott
     
  2. jcsd
  3. Sep 30, 2006 #2
    Indeed it does. In fact, it's the reason that metals have their particular properties, is that the exclusion principle leads to the Fermi surface and such, which is a major player in condensed matter physics.
     
  4. Oct 1, 2006 #3

    ZapperZ

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    Look at the density of states of conduction electrons, or even their momentum distribution. The Fermi-Dirac statistics are well-obeyed.

    Zz.
     
  5. Oct 1, 2006 #4

    Dr Transport

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    Take a look at Seitz's book on solids, it explains everything you are asking about.
     
  6. Oct 1, 2006 #5

    Gokul43201

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    To be specific, in the absence of an applied magnetic field, the conduction electrons do obey the Exclusion Principle.
     
  7. Oct 2, 2006 #6
    Thanks everyone,

    But Gokul what about metals in the presence of an applied magnetic field? How do atoms retain their identity? Do they simply 'move' to the side of the metal of which their spin is same?

    Thanks,
    -scott
     
  8. Oct 2, 2006 #7

    ZapperZ

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    If I'm guessing what Gokul is trying to convey, it is that the conduction electrons in metals is normally a DEGENERATE electron gas. It means that the occupation number per state is two, instead of one, due to each state having a spin up and spin down electron. It is only upon the application of a magnetic field is the degeneracy removed and each spin orientation split in energy level.

    Zz.
     
  9. Oct 2, 2006 #8
    Ok I think I understand. So the Pauli Exclusion principle is not violated since the only time two electrons from the same orbital can have same spins is when one moves up to a higher energy level, maintaining individual quantum numbers. Since electrons have a tendency to occupy lower energy states, some resistence comes from the process of forcing an electron into a higher energy level. Now certain materials called diamagnets never conform to a applied magnetic field because the electrons do not have a higher energy level to jump to, correct?

    Thanks,
    -scott
     
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