Abstract

Further extensions are made to a previously developed analysis for the two-time correlation functions in anharmonic lattices within the first-order self-consistent phonon approximation. This stationary-variation approximation is shown to represent an energy minimum if and only if the one-phonon response is stable. An explicit expression is exhibited for the two-phonon response and is interpreted as yielding an effective interaction between phonons. It is shown that the first-order approximation is not fully adequate for describing transport properties (e. g., thermal conductivity) or for investigating resonances or bound states of the two phonons. The distortion of the one-phonon peak in the inelastic-neutron or Raman-scattering cross section due to the finite size of the momentum transfer is investigated in more detail than the previous analysis.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.