Abstract
A structural phase transition is studied which is driven by a soft phonon. It is assumed that atT=0°K all harmonic lattice modes are stable and that the quartic interaction between optical phonons has a negative coupling constant for a symmetry point of the Brillouin zone. It is then shown that with increasing temperature the optical mode corresponding to this symmetry point softens. An instability of the lattice arises for a finite soft-mode frequency ν. The problem is studied by calculating ν self-consistently within the chain approximation.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
