Date of this Version
Physical Review B
We present an analytical calculation of the spin-wave spectrum of the Jahn-Teller system LaTiO3. The calculation includes all superexchange couplings between nearest-neighbor Ti ions allowed by the space-group symmetries: The isotropic Heisenberg couplings and the antisymmetric (Dzyaloshinskii-Moriya) and symmetric anisotropies. The calculated spin-wave dispersion has four branches, two nearly degenerate branches with small zone-center gaps and two practically indistinguishable high-energy branches having large zone-center gaps. The two lower-energy modes are found to be in satisfying agreement with neutron-scattering experiments. In particular, the experimentally detected approximate isotropy in the Brillouin zone and the small zone-center gap are well reproduced by the calculations. The higher-energy branches have not been detected yet by neutron scattering but their zone-center gaps are in satisfying agreement with recent Raman data.
Schmitz, R., Entin-Wohlman, O., Aharony, A., Harris, A., & Müller-Hartmann, E. (2005). Spin-Wave Spectrum of the Jahn-Teller System LaTiO3. Physical Review B, 71 214438-1-214438-11. http://dx.doi.org/10.1103/PhysRevB.71.214438
Date Posted: 12 August 2015
This document has been peer reviewed.