Hexagonal Structure of Baby Skyrmion Lattices

TL;DR

This paper investigates the crystalline structure of baby Skyrmions at zero temperature, finding that a hexagonal lattice minimizes energy and causes Skyrmion splitting into quarter-Skyrmions, outperforming rectangular arrangements.

Contribution

It demonstrates that baby Skyrmions form a hexagonal lattice at zero temperature, with lower energy than rectangular lattices, and reveals Skyrmion splitting into quarter-Skyrmions in this configuration.

Findings

Hexagonal lattice minimizes energy for baby Skyrmions.

Skyrmions split into quarter-Skyrmions in the hexagonal lattice.

Hexagonal arrangement has lower energy than rectangular lattice.

Abstract

We study the zero-temperature crystalline structure of baby Skyrmions by applying a full-field numerical minimization algorithm to baby Skyrmions placed inside different parallelogramic unit-cells and imposing periodic boundary conditions. We find that within this setup, the minimal energy is obtained for the hexagonal lattice, and that in the resulting configuration the Skyrmion splits into quarter-Skyrmions. In particular, we find that the energy in the hexagonal case is lower than the one obtained on the well-studied rectangular lattice, in which splitting into half-Skyrmions is observed.