Phenomenological Description of the Acoustic Phonon Branch of K_2SeO_4
Ferroelectrics Volume 302
Page 147-150
published_at 2004
Title
Phenomenological Description of the Acoustic Phonon Branch of K_2SeO_4
Creators
Mashiyama Hiroyuki
Creator Keywords
Phenomenological approach
acoustic branch
K_2SeO_4
A phenomenological approach is used in investigating dispersion of the acoustic phonon branch of K_2SeO_4 in the extended zone scheme. The dispersion is expressed through coefficients of a simple thermodynamic potential. According to symmetry of the crystal (D_2h = mmm) the Lifshitz-type invariant exists in the potential. This invariant is responsible for the linear and dynamical interaction of the acoustic and optical branches. The soft optical branch lowering with decreasing temperature forces to lower the acoustic branch which becomes zero at some value of the wave vector.
Languages
eng
Resource Type
journal article
Publishers
Taylor and Francis
Date Issued
2004
File Version
Author’s Original
Access Rights
open access
Relations
[ISSN]0015-0193
[NCID]AA00644949
[isVersionOf]
[URI]http://www.tandf.co.uk/journals/titles/00150193.asp
Schools
大学院理工学研究科（理学）