Dynamic probes of quantum spin chains with the Dzyaloshinskii-Moriya interaction

TL;DR

This paper investigates how the Dzyaloshinskii-Moriya interaction influences the dynamic properties of a quantum spin-1/2 XY chain, providing analytical and numerical insights into its effects on excitation continua across different conditions.

Contribution

It offers an analytical calculation of the transverse spin structure factor and explores the Dzyaloshinskii-Moriya interaction's impact on excitation continua in quantum spin chains.

Findings

Dzyaloshinskii-Moriya interaction modifies the two-fermion excitation continuum.

Dynamic structure factors are affected by many-fermion excitations.

Effects vary with magnetic field strength and temperature.

Abstract

We consider the spin-1/2 anisotropic XY chain in a transverse (z) field with the Dzyaloshinskii-Moriya interaction directed along z-axis in spin space to examine the effect of the Dzyaloshinskii-Moriya interaction on the zz, xx and yy dynamic structure factors. Using the Jordan-Wigner fermionization approach we analytically calculate the dynamic transverse spin structure factor. It is governed by a two-fermion excitation continuum. We analyze the effect of the Dzyaloshinskii-Moriya interaction on the two-fermion excitation continuum. Other dynamic structure factors which are governed by many-fermion excitations are calculated numerically. We discuss how the Dzyaloshinskii-Moriya interaction manifests itself in the dynamic properties of the quantum spin chain at various fields and temperatures.