Dynamical and static spin structure factors of Heisenberg antiferromagnet on honeycomb lattice in the presence of Dzyaloshinskii-Moriya interaction

TL;DR

This paper theoretically investigates how Dzyaloshinskii-Moriya interaction and magnetic fields influence the static and dynamical spin structure factors in a Heisenberg antiferromagnet on a honeycomb lattice, revealing shifts in peak positions and intensity variations.

Contribution

It introduces a bosonic model approach to analyze spin structure factors in the presence of Dzyaloshinskii-Moriya interaction and magnetic field, including effects of spatial anisotropy and next nearest neighbor exchange.

Findings

Peak in dynamical transverse spin structure factor shifts to higher frequency with magnetic field.

Dzyaloshinskii-Moriya interaction decreases the intensity of the dynamical transverse spin structure factor.

Static transverse structure factor decreases monotonically with magnetic field and temperature.

Abstract

We have theoretically studied the spin structure factors of Heisenberg model on honeycomb lattice in the presence of longitudinal magnetic field, i.e. magnetic field perpendicular to the honeycomb plane, and Dzyaloshinskii-Moriya interaction. The possible effects of next nearest neighbor exchange constant are investigated in terms of anisotropy in the Heisenberg interactions. This spatial anisotropy is due to the difference between nearest neighbor exchange coupling constant and next nearest neighbor exchange coupling constant. The original spin model hamiltonian is mapped to a bosonic model via a hard core bosonic transformation where an infinite hard core repulsion is imposed to constrain one boson occupation per site. Using Green's function approach, the energy spectrum of quasiparticle excitation has been obtained. The spectrum of the bosonic gas has been implemented in order to obtain two particle propagator which corresponds to spin structure factor of original Heisenberg chain model Hamiltonian. The results show the position of peak in the dynamical transverse spin structure factor at fixed value for Dzyaloshinskii Moriya interaction moves to higher frequency with magnetic field. Also the intensity of dynamical transverse spin structure factor is not affected by magnetic field. However the Dzyaloshinskii Moriya interaction strength causes to decrease the intensity of dynamical transverse spin structure factor. The increase of magnetic field does not varied the frequency position of peaks in dynamical longitudinal spin susceptibility however the intensity reduces with magnetic field. Our results show static transverse structure factor is found to be monotonically decreasing with magnetic field and temperature for different vlaues of next nearest neighbor coupling exchange constant.