Brillouin-scattering observation of the TA-TO coupling in SrTiO3
Brillouin scattering from transverse-acoustic modes of SrTiO3 is observed, while the frequencies of the soft polar modes are remeasured with hyper-Raman scattering. It is shown that an anomalous decrease of sound velocities at low temperatures results from the.coupling of the strain with the gradient of the electrical polarization fluctuations. The corresponding anomaly in the acoustic width indicates an inhomogeneous broadening of the soft polar mode.
Hehlen, B Univ Montpellier 2, Lab Verres, CNRS, UMR 5587, F-34095 Montpellier 5, France Univ Montpellier 2, Lab Verres, CNRS, UMR 5587, F-34095 Montpellier 5, France Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France Ecole Polytech Fed Lausanne, Lab Ceram, CH-1015 Lausanne, Switzerland Hokkaido Univ, Res Inst Elect Sci, Sapporo, Hokkaido 060, Japan
Cited References Count:32
Record created on 2006-08-21, modified on 2016-08-08