Abstract
The method of Buyers and Holden (1975) for calculating excitation frequencies in singlet ground state ferromagnets is extended to systems undergoing cooperative Jahn-Teller transitions. The electron-lattice interaction is treated by the displaced operator technique. It is shown that the full response of the system always diverges at the molecular field transition temperature, as expected, provided account is taken of the zero-frequency transitions. Difficulties previously encountered in applying the displaced operator method to situations where there is coupling to non-commuting electron operators are avoided by using an exact result for the phonon equation of motion. Damping is added in a phenomenological way and estimates are made of the relaxation times in the theory. The excitation frequencies are calculated for a simple model of PrAlO3.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.