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Dispersion curves

  1. Sep 10, 2009 #1
    what can be interpret from dispersion curve of phonon?how to find whether a phonon can loose all its energy to a neutron from dispersion curves?are there dispersion curves for other atom apart from phonon?
     
  2. jcsd
  3. Sep 11, 2009 #2
    The quanta of lattice vibrations are the phonons, and the dispersion tells what allowed energies exist for various wavevectors. Also, if it happens that you have negative (imaginary) frequencies, then this tells you that you have a lattice instability.

    AFAIK, all phonons can be excited by neutrons. You might be able to calculate a phonon cross-section to see what phonons will be most easily observed, but I don't know anything about how or if that is done.

    What do you mean? There's dispersion curves for electronic excitations (measured by ARPES), spin waves (measured by neutrons) and anything else which is k-dependent.
     
  4. Sep 11, 2009 #3
    thank very much.
     
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