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What is a phonon?

  1. Sep 23, 2013 #1
    We have studied elastic waves in solids, standing waves in solid, heat capacity due to oscillation modes of individual atoms in a solid etc etc. And all these are put in the chapter called phonons in my book. So what are phonons basically? Are they just any kind of wave oscillatory motion that can occur within a solid? Because surely any wave in a solid need to be standing etc etc.
  2. jcsd
  3. Sep 23, 2013 #2


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    Loosely speaking photons are "quantized sound waves", i.e., the quantum description of collective lattice vibrations of a solid. Wikipedia gives a pretty nice starting point:

  4. Sep 23, 2013 #3


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  5. Sep 23, 2013 #4
    They are quanta of sound waves just as photons are quanta of electromagnetic waves
  6. Sep 23, 2013 #5
    Phonons are bundles [quanta] of energy associated with lattice vibrations...that is, oscillations associated with the degrees of freedom in the structure of a material....

    From Zapper:
    https://www.physicsforums.com/showthread.php?p=899393#post899393 [Broken]

    Last edited by a moderator: May 6, 2017
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