Topological order generated by random field in a 2D exchange model

Abstract

We study a 2D exchange model with a weak static random field on lattices containing over one hundred million spins. Ferromagnetic correlations persist on the Imry-Ma scale inversely proportional to the random-field strength and decay exponentially at greater distances. We find that the average energy of the correlated area is close to the ground-state energy of a skyrmion, while the topological charge of the area is close to $\pm 1$. Correlation function of the topological charge density exhibits oscillations with a period determined by the ferromagnetic correlation length, while its Fourier transform exhibits a maximum. These findings suggest that static randomness transforms a 2D ferromagnetic state into a skyrmion-antiskyrmion glass.

5 pages, 3 figures

References in corpus (8)

• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Skyrmions in Magnetic Multilayers
• On Larkin-Imry-Ma State of 3He-A in Aerogel
• Resonant properties of dipole skyrmions in amorphous Fe/Gd multilayers
• Experimental evidence for a Bragg glass density wave phase in a transition-metal dichalcogenide
• Liquid crystal cells with "dirty" substrates
• Instanton Glass Generated by Noise in a Josephson-Junction Array
• Effect of Dilute Random Field on Continuous-Symmetry Order Parameter

Cited by in corpus (13)

• Skyrmion-Skyrmion Interaction in a Magnetic Film
• Stability of Biskyrmions in Centrosymmetric Magnetic Films
• Whirling interlayer fields as a source of stable topological order in moiré CrI3
• Thermal Creation of Skyrmions in Ferromagnetic Films with Perpendicular Anisotropy and Dzyaloshinskii-Moriya Interaction
• Biskyrmions Lattices in Centrosymmetric Magnetic Films
• ${}^3$He Universe 2020
• Absorption of Microwaves by Random-Anisotropy Magnets
• Spin, orbital, Weyl and other glasses in topological superfluids
• Nonlinear and Thermal Effects in the Absorption of Microwaves by Random Magnets
• Random Anisotropy Magnet at Finite Temperature
• Integral Absorption of Microwave Power by Random-Anisotropy Magnets
• Energy minima and ordering in ferromagnets with quenched randomness
• Static and Microwave Properties of Amorphous Magnets Near Saturation