Evolution of Skyrmion Crystals in Fe$_{0.5}$Co$_{0.5}$Si-Like Quasi-Two-Dimensional Ferromagnets Driven by External Magnetic Field and Temperature

TL;DR

This study uses a quantum computational approach to explore how external magnetic fields and temperature influence skyrmion crystal formations in a quasi-two-dimensional ferromagnetic system, aligning with experimental observations.

Contribution

It introduces a quantum model that qualitatively reproduces experimental skyrmion behaviors, especially for small skyrmion sizes, improving upon classical models.

Findings

Induction of hexagonal skyrmion crystal patterns under weak magnetic fields.

Evolution of spin configurations with changing magnetic field and temperature.

Quantum model aligns with experimental long-period skyrmion observations.

Abstract

Magnetic skyrmions have attracted great research interest in recent years due to their exotic physical properties, scientific merit and potential applications in modern technology. Here, we apply a quantum computational method to investigate the spin configurations of Fe$_{0.5}$Co$_{0.5}$Si-Like quasi-two-dimensional ferromagnetic system with co-existence of Dzyaloshinsky-Moriya and Heisenberg exchange interactions. We find that within a weak magnetic field perpendicular to the film plane, skyrmion crystal (SkX) of hexagonal-close-packed pattern can be induced, the spin configurations evolve with applied magnetic field and temperature. This quantum model, if scaled, is able to qualitatively reproduce the experimental results of SkX with long periodicity, especially, when the skyrmion size is around a few nano-meters in diameter, it is expected to be more accurate than the classical ones.