Spin-wave energy dispersion of a frustrated spin-1/2 Heisenberg antiferromagnet on a stacked square lattice

TL;DR

This study investigates how interlayer coupling and spatial anisotropy influence spin-wave excitation spectra in a three-dimensional frustrated spin-1/2 Heisenberg antiferromagnet, revealing significant second-order corrections and qualitative similarities with 2D systems.

Contribution

It provides a detailed analysis of spin-wave spectra considering interlayer coupling and anisotropy using second-order expansion, highlighting features relevant for experimental measurements.

Findings

Second-order corrections significantly affect spin-wave energies.

3D spectra share qualitative features with 2D square lattice HAFM.

Features identified can help measure interlayer coupling and frustration.

Abstract

Effects of interlayer coupling and spatial anisotropy on spin-wave excitation spectra of a three-dimensional spatially anisotropic, frustrated spin-$\half$ Heisenberg antiferromagnet (HAFM) is investigated for the two ordered phases using second-order spin-wave expansion. We show that the second-order corrections to the spin-wave energies are significant and find that the energy spectra of the three-dimensional HAFM shares similar qualitative features with the energy spectra of the two-dimensional HAFM on a square lattice. We also discuss the features that can provide experimental measures for the strength of the interlayer coupling, spatial anisotropy parameter, and magnetic frustration.