Low-frequency response of KDP-like crystals in the spin-phonon model
- 7 August 1974
- journal article
- Published by IOP Publishing in Journal of Physics C: Solid State Physics
- Vol. 7 (15) , 2721-2728
- https://doi.org/10.1088/0022-3719/7/15/021
Abstract
The pseudo-spin model of ferroelectric crystals like KDP is extended to include coupling between the soft spin-wave mode and fluctuations in the phonon numbers via spin-two phonon terms in the hamiltonian. It is shown that this provides an explanation of the temperature dependence of the width of the Raman scattering response and predicts a central peak in some circumstances. The magnitude of the coupling may be shown to be related to the splitting of the E modes below the transition temperature since this arises from the same terms. The frequency dependence of the elastic constants is also discussed.Keywords
This publication has 14 references indexed in Scilit:
- Paraelectric, piezoelectric and pyroelectric crystals: II Phase transitionsJournal of Physics C: Solid State Physics, 1973
- Paraelectric, piezoelectric and pyroelectric crystals: I. Dielectric propertiesJournal of Physics C: Solid State Physics, 1973
- Dynamics of order-disorder-type ferroelectrics and anti-ferroelectricsAdvances in Physics, 1972
- Raman scattering and theoretical studies of Jahn—Teller induced phase transitions in some rare-earth compoundsProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1972
- 11.—The Symmetry of Atomic Vibrations in KH2PO4Proceedings of the Royal Society of Edinburgh: Section A Mathematics, 1972
- Acoustic anomalies in Jahn-Teller coupled systemsJournal of Physics C: Solid State Physics, 1971
- Ultrasonic Velocity and Attenuation in KPPhysical Review B, 1969
- Brillouin-Scattering Study of the Ferroelectric Transition in KPPhysical Review Letters, 1968
- Dynamical Theory of the Phase Transition in KH2PO4-Type Ferroelectric CrystalsJournal of the Physics Society Japan, 1968
- Collective motions of hydrogen bondsSolid State Communications, 1963