Spin-wave analysis of the XXZ Heisenberg model with Dzyaloshinskii-Moriya interaction

摘要

The effect of the Dzyaloshinskii-Moriya interaction on the stability of the Neel phase and the energy gap for the XXZ Heisenberg model on a d-dimensional hypercubic lattice is investigated using the linear spin-wave theory. In one- dimension, the disordered phase disappears above a critical value of the spin- axis anisotropy. In two-dimension, the instability of the Neel order occurs below a critical value of the easy-axis anisotropy. We find that for all d- dimensional systems, the energy gap vanishes above a critical value of the DM interaction. (author) 23 refs, 5 figs