Stability and dynamics of free magnetic polarons

TL;DR

This paper investigates the stability and movement of free magnetic polarons using Monte Carlo simulations, revealing temperature effects and tunneling behavior, and compares these findings to previous mean-field predictions.

Contribution

It provides a detailed Monte Carlo analysis of free magnetic polarons, highlighting differences from mean-field results and exploring their dynamical properties.

Findings

Polaron diffusion depends on temperature

Identification of a crossover to tunneling regime

Qualitative agreement with mean-field analysis

Abstract

The stability and dynamics of a free magnetic polaron are studied by Monte Carlo simulation of a classical two-dimensional Heisenberg model coupled to a single electron. We compare our results to the earlier mean-field analysis of the stability of the polaron, finding qualitative similarity but quantitative differences. The dynamical simulations give estimates of the temperature dependence of the polaron diffusion, as well as a crossover to a tunnelling regime.