Magnetic excitations in two-dimensional antiferromagnets with easy-plane anisotropy

30 May 1980

journal article
Published by IOP Publishing in Journal of Physics C: Solid State Physics

Vol. 13 (15) , 2925-2943
https://doi.org/10.1088/0022-3719/13/15/016

Abstract

The temperature dependence of the magnon energies in two-dimensional antiferromagnets with easy-plane anisotropy has been investigated by means of a Green function approach. A preliminary treatment of the non-diagonal effects of the anisotropy is made and the Hartree-Fock magnon energies are obtained by a first-order perturbation theory in the anisotropy. These results are applied to the planar antiferromagnets K₂FeF₄ and Rb₂FeF₄. In the first compound, satisfactory agreement is found with the experimental temperature dependence of the magnetisation as well as the one-magnon and two-magnon Raman scattering data. The case of Rb₂FeF₄ (where only zone-boundary features are accounted for) is critically discussed.

Keywords

This publication has 19 references indexed in Scilit:

Kinematic consistency in anisotropic ferromagnets
Journal of Physics C: Solid State Physics, 1979
Diagonalization of the quadratic boson hamiltonian
Physica A: Statistical Mechanics and its Applications, 1978
Determination of zone-boundary magnon energy and damping in RbMnF3 by means of light scattering experiments
Solid State Communications, 1978
Canonical transform method for treating strongly anisotropic magnets
Physical Review B, 1977
Light scattering in heisenberg antiferromagnets
La Rivista del Nuovo Cimento, 1976
Experiments on simple magnetic model systems
Advances in Physics, 1974
Theory of Two-Magnon Raman Scattering in the Ordered Region for Cubic Antiferromagnets
Physical Review B, 1973
Two-Magnon Raman Scattering and Exchange Interactions in Antiferromagnetic KNi $F_{3}$ and $K_{2}$ Ni $F_{4}$ and Ferrimagnetic RbNi $F_{3}$
Physical Review B, 1971
Neutron Scattering Investigation of Phase Transitions and Magnetic Correlations in the Two-Dimensional Antiferromagnets $K_{2}$ Ni $F_{4}$ , ${Rb}_{2}$ Mn $F_{4}$ , ${Rb}_{2}$ Fe $F_{4}$
Physical Review B, 1970
Neutron Scattering from $K_{2}$ Ni $F_{4}$ : A Two-Dimensional Heisenberg Antiferromagnet
Physical Review Letters, 1969