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arXiv · 1412.0739

Dissipation processes in the insulating skyrmion compound Cu2OSeO3

I. Levatić·V. Šurija·H. Berger·I. Živković
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Abstract

We present a detailed study of the phase diagram surrounding the skyrmion lattice (SkL) phase of Cu2OSe2O3 using high-precision magnetic ac susceptibility measurements. An extensive investigation of transition dynamics around the SkL phase using the imaginary component of the susceptibility revealed that at the conical-to-SkL transition a broad dissipation region exists with a complex frequency dependence. The analysis of the observed behavior within the SkL phase indicates a distribution of relaxation times intrinsically related to SkL. At the SkL-to-paramagnet transition a narrow first-order peak is found that exhibits a strong frequency and magnetic field dependence. Surprisingly, very similar dependence has been discovered for the first-order transition below the SkL phase, i.e. where the system enters the helical and conical state(s), indicating similar processes across the order-disorder transition.

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I. Levatić, V. Šurija, H. Berger, I. Živković. 2014-12-01. Dissipation processes in the insulating skyrmion compound Cu2OSeO3. https://doi.org/10.1103/physrevb.90.224412

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