Monte Carlo Simulation of Magnetization Reversal in Fe Sesquilayers on W(110)

TL;DR

This paper uses Monte Carlo simulations with a kinetic Ising model to study magnetization reversal in Fe sesquilayers on W(110), revealing the influence of second-layer islands and thermal fluctuations on coercivity.

Contribution

It introduces a simulation approach that captures domain-wall dynamics and pinning effects, providing new insights beyond previous micromagnetic models.

Findings

Simulated coercivity dependence matches experimental data.

Second-layer islands act as pinning centers.

Thermal fluctuations significantly influence domain-wall motion.

Abstract

Iron sesquilayers grown at room temperature on W(110) exhibit a pronounced coercivity maximum near a coverage of 1.5 atomic monolayers. On lattices which faithfully reproduce the morphology of the real films, a kinetic Ising model is utilized to simulate the domain-wall motion. Simulations reveal that the dynamics is dominated by the second-layer islands, which act as pinning centers. The simulated dependencies of the coercivity on the film coverage, as well as on the temperature and the frequency of the applied field, are very similar to those measured in experiments. Unlike previous micromagnetic models, the presented approach provides insight into the dynamics of the domain-wall motion and clearly reveals the role of thermal fluctuations.