Colloquium: Quantum skyrmionics

TL;DR

This paper explores the quantum aspects of magnetic skyrmions, focusing on how their topological properties influence their quantum translational dynamics and connecting these phenomena to broader quantum theories.

Contribution

It introduces a framework for understanding quantum interference effects in skyrmion motion, bridging classical micromagnetic models with quantum mechanics and topological field theories.

Findings

Quantum interference affects skyrmion translational dynamics.

Topological charge influences quantum behavior of skyrmions.

Connections established with noncommutative quantum mechanics and quantum Hall effect.

Abstract

Skyrmions are topological solitons that emerge in many physical contexts. In magnetism, they appear as textures of the spin-density field stabilized by different competing interactions and characterized by a topological charge that counts the number of times the order parameter wraps the sphere. They can behave as classical objects, when the spin texture varies slowly on the scale of the microscopic lattice of the magnet. However, the fast development of experimental tools to create and stabilize skyrmions in thin magnetic films has lead to a rich variety of textures, sometimes of atomistic sizes. In this article, we discuss, in a pedagogical manner, how to introduce quantum interference in the translational dynamics of skyrmion textures, starting from the micromagnetic equations of motion for a classical soliton. We study how the nontrivial topology of the spin texture manifests in the semiclassical regime, when the microscopic lattice potential is treated quantum-mechanically, but the external driving forces are taken as smooth classical perturbations. We highlight close relations to the fields of noncommutative quantum mechanics, Chern-Simons theories, and the quantum Hall effect.