Nematic and smectic stripe phases and stripe-SkX transformations

TL;DR

This paper demonstrates controlled manipulation and transformation of stripe skyrmions, helical states, and skyrmion crystals in chiral magnetic films using patterned fields and spin-transfer torques, revealing new phase control methods.

Contribution

It introduces precise control techniques for stripe skyrmions and their transformations, including generating nematic and smectic phases and creating complex structures like UST mosaics.

Findings

Controlled creation of stripe phases and skyrmion structures.

Transformation between helical states and skyrmion crystals.

External fields enable shape and phase manipulation.

Abstract

Based on the findings of stripe skyrmions and the metastability of a state of an arbitrary number of skyrmions, precisely controlled manipulation of stripe skyrmions in pre-designed structures and mutual transformation between helical states and skyrmion crystals (SkXs) are demonstrated in chiral magnetic films. As a proof of the concept, we show how to use patterned magnetic fields and spin-transfer torques (STTs) to generate nematic and smectic stripe phases, as well as "UST" mosaic from three curved stripe skyrmions. Cutting one stripe into many pieces and coalescing several skyrmions into one by various external fields are good ways to transform helical states and SkXs from each other.