Collective excitations in the anharmonic crystal

We consider a lattice model of an anharmonic crystal and compute the isothermal ( χ T ) and adiabatics ( χ S ) susceptibilities for the lattice displacement below T c. A detailed analysis is given in terms of the dimension of the lattice and a decay parameter of the harmonic force. It turns out that...

Full description

Saved in:
Bibliographic Details
Published in:Physica A 1995-05, Vol.215 (3), p.394-404
Main Authors: Verbeure, A, Zagrebnov, V.A
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We consider a lattice model of an anharmonic crystal and compute the isothermal ( χ T ) and adiabatics ( χ S ) susceptibilities for the lattice displacement below T c. A detailed analysis is given in terms of the dimension of the lattice and a decay parameter of the harmonic force. It turns out that there is a phase-space region for which 0 < χ T / χ S < 1, indicating breaking of ergodicity, and a region for which χ T is finite, indicating the presence of a plasmon frequency due to the anharmonicity.
ISSN:0378-4371
1873-2119
DOI:10.1016/0378-4371(94)00260-Z