Observation of a new light-induced skyrmion phase in the Mott insulator Cu2OSeO3

TL;DR

This paper reports the discovery of a new light-induced skyrmion phase in Cu2OSeO3, achieved through femtosecond laser pulses, which extends the skyrmion stability range and has implications for data storage.

Contribution

The study reveals a novel non-equilibrium skyrmion phase in Cu2OSeO3 induced by ultrafast laser pulses, expanding understanding of skyrmion control via magnetoelastic effects.

Findings

Identified a new skyrmion phase accessible only through optical excitation.

Demonstrated the phase's stability over minutes.

Linked the creation mechanism to magnetoelastic effects.

Abstract

We report the discovery of a novel skyrmion phase in the multiferroic insulator Cu2OSeO3 for magnetic fields below the equilibrium skyrmion pocket. This phase can be accessed by exciting the sample out of equilibrium with near-infrared (NIR) femtosecond laser pulses but can not be reached by any conventional field cooling protocol. From the strong wavelength dependence of the photocreation process and via spin dynamics simulations, we identify the magnetoelastic effect as the most likely photocreation mechanism. This effect results in a transient modification of the magnetic interaction extending the equilibrium skyrmion pocket to lower magnetic fields. Once created, the skyrmions rearrange and remain stable over a long time, reaching minutes. The presented results are relevant for designing high-efficiency non-volatile data storage based on magnetic skyrmions.