Spin Dynamics in Pyrochlore Heisenberg Antiferromagnets

TL;DR

This paper investigates the low-temperature spin dynamics of classical Heisenberg antiferromagnets on the pyrochlore lattice, combining simulations and a solvable stochastic model to understand relaxation behaviors.

Contribution

It introduces a stochastic model that accurately reproduces the wavevector and frequency dependence of the dynamical structure factor in pyrochlore antiferromagnets.

Findings

Spin correlations relax at a wavevector-independent rate proportional to temperature.

The stochastic model captures key features of the precessional dynamics.

Simulation results detail the wavevector and frequency dependence of the dynamical structure factor.

Abstract

We study the low temperature dynamics of the classical Heisenberg antiferromagnet with nearest neighbour interactions on the pyrochlore lattice. We present extensive results for the wavevector and frequency dependence of the dynamical structure factor, obtained from simulations of the precessional dynamics. We also construct a solvable stochastic model for dynamics with conserved magnetisation, which accurately reproduces most features of the precessional results. Spin correlations relax at a rate independent of wavevector and proportional to temperature.