Multiple Helical Spin Density Waves and Magnetic Skyrmions in Itinerant Electron System

TL;DR

This paper investigates the emergence and stability of magnetic skyrmions and multiple helical spin density waves in itinerant electron systems, demonstrating their stabilization without Dzyaloshinskii-Moriya interaction through phenomenological and microscopic theories.

Contribution

It introduces a new understanding of skyrmion stabilization in itinerant systems using Ginzburg-Landau and Hartree-Fock theories, without relying on Dzyaloshinskii-Moriya interaction.

Findings

Skyrmion structures can emerge as MHSDW in itinerant electron systems.

Skyrmions are stabilized on fcc lattices near half-filling.

Antiferromagnetic skyrmion structures are theoretically confirmed.

Abstract

Magnetic structures and their stability of the multiple helical spin density waves (MHSDW) and related magnetic skyrmions in itinerant electron system have been investigated on the basis of both the phenomenological and microscopic theories. It is shown by using the Ginzburg-Landau (GL) theory and the Application Visualization System (AVS) that the magnetic skyrmion structures emerge as a MHSDW and can be stabilized in itinerant electron system on the fcc lattice even if there is no Dzyaloshinskii-Moriya interaction. Moreover, by using the generalized Hartree-Fock theory for the Hubbard model, the antiferromagnetic skyrmion structure found in the GL theory is shown to be stabilized on the fcc lattice in the vicinity of the half-filled electron number.