Spin Excitations in the Noncollinear Magnetic Phase of LaMn2O5

Abstract

Spin dynamics of the LaMn₂O₅ compound, which contains manganese ions with different charges in two crystallographically different positions, has been investigated. The description of the dynamics is based on the equations of motion for the irreducible spin operators. It has been shown that the presence of a noncollinear antiferromagnetic ordering of manganese ions in the different crystallographic positions leads to the necessity of not only the determination of the frequencies of spin excitations, but also the formulation of conditions for the stability of the magnetic state relative to which the dynamic processes are considered.