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Fermi level

  1. Jun 2, 2015 #1
    Hi, a question please:

    Do all metallic substances have an equal Fermi energy level (at a constant T) ?
    If not, what will happen (before equilibrium) if one "fuses" together two bulks of metal with different Fermi
    levels (as in a PN junction) ?

    Since there's an abundance of energy states available around the Fermi level in metals, I would consequently expect electrons to flow between the bulks until an equilibrium is reached. On the other hand, I sense a hole in my little theory here.

    Many thanks.

  2. jcsd
  3. Jun 2, 2015 #2
    No, they don't. Electrons will indeed be transferred between the two metals. See Peltier effect.
  4. Jun 2, 2015 #3


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    There's something called a "contact potential" when such metals are in contact with each other, very much similar to a PN junction as you suspected.

    This effect is made use of in the Kelvin Probe technique of measuring contact potential and Fermi energy in metals.

  5. Nov 13, 2016 #4
    To be more explicit, the conduction band and insulation band overlap for two metals allowing for electrons to move freely in a metal.
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