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arXiv · 1607.08177

Magnetic relaxation phenomena in Cu$_2$OSeO$_3$ and phase diagram

F. Qian·H. Wilhelm·A. Aqeel·T. T. M. Palstra·A. J. E. Lefering·E. H. Brück·C. Pappas
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Abstract

We present an investigation of the magnetic field-temperature phase diagram of Cu$_2$OSeO$_3$ based on DC magnetisation and AC susceptibility measurements covering a broad frequency range of four orders of magnitude, from very low frequencies reaching 0.1 Hz up to 1 kHz. The experiments were performed in the vicinity of $T_C=58.2$ K and around the skyrmion lattice A-phase. At the borders between the different phases the characteristic relaxation times reach several milliseconds and the relaxation is non-exponential. Consequently the borders between the different phases depend on the specific criteria and frequency used and an unambiguous determination is not possible.

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F. Qian, H. Wilhelm, A. Aqeel, T. T. M. Palstra, A. J. E. Lefering, E. H. Brück, C. Pappas. 2016-07-27. Magnetic relaxation phenomena in Cu$_2$OSeO$_3$ and phase diagram. https://arxiv.org/abs/1607.08177

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