Skyrmion Phase Control by Magnetic Dipole-Dipole Interaction and Electric Field in Centrosymmetric Materials

Abstract

Establishing precise control over the helicity and spatial configuration of magnetic skyrmions will be essential to realize their promise in classical, analog and quantum computation applications. In this work, we explore the role of magnetic dipole-dipole interactions, external electric fields, and magnetic fields in controlling these parameters within a triangular lattice centrosymmetric skyrmion host. We demonstrate that dipole-dipole interactions strongly favor Bloch helicity. Notably, a zero magnetic field skyrmion phase appears upon raising the dipole-dipole coupling strength, with substantial potential for cost-effective quantum device applications. We also report the emergence of a meron/antimeron lattice phase, in the absence of any Dzyaloshinskii-Moriya interaction. In contrast, applied electric fields stabilize high density N\'eel skyrmion crystals. The interplay between dipole-dipole interactions and external electric fields creates a continuous transition between the two skyrmion types, rather than an abrupt switch. Applied electric fields can therefore be used as a continuous tuning mechanism for skyrmion helicity, and hence a control handle for tuning two-level systems in skyrmion qubits.