Stability of Skyrmion Crystal Phase in Centrosymmetric Distorted Triangular-Lattice Antiferromagnets

TL;DR

This study demonstrates the stability of skyrmion crystal phases in centrosymmetric distorted triangular-lattice antiferromagnets through numerical simulations, revealing robustness under specific interactions and tunability of skyrmion types via anisotropic exchange.

Contribution

It provides the first detailed numerical analysis of skyrmion crystal stability in centrosymmetric orthorhombic systems with uniaxial distortion, highlighting the role of momentum-space interactions and anisotropic exchange.

Findings

Skyrmion crystals are stable with double-Q momentum structure.

Anti-type skyrmions can be realized by tuning exchange interactions.

Skyrmion stability persists under uniaxial lattice distortion.

Abstract

The stability of a magnetic skyrmion crystal in a centrosymmetric orthorhombic lattice system is numerically investigated. By performing the simulated annealing for an effective spin model with the momentum-resolved interaction on a uniaxially distorted triangular lattice, we find that the skyrmion crystal is robustly realized when dominant interaction channels consist of the double-$Q$ structure in momentum space. Moreover, we show that an anti-type skyrmion crystal with the opposite skyrmion number is obtained by tuning the sign of the bond-dependent anisotropic exchange interaction that originates from the relativistic spin-orbit coupling.