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arXiv · 1705.07776

Monte Carlo modeling the phase diagram of magnets with the Dzyaloshinskii - Moriya interaction

A. M. Belemuk·S. M. Stishov
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Abstract

We use classical Monte Carlo calculations to model the high-pressure behavior of the phase transition in the helical magnets. We vary values of the exchange interaction constant J and the Dzyaloshinskii-Moriya interaction constant D, which is equivalent to changing spin-spin distances, as occurs in real systems under pressure. The system under study is self-similar at D/ J = constant, and its properties are defined by the single variable J / T , where T is temperature. The existence of the first order phase transition critically depends on the ratio D / J. A variation of J strongly affects the phase transition temperature and width of the fluctuation region (the hump) as follows from the system self-similarity. The high-pressure behavior of the spin system depends on the evolution of the interaction constants J and D on compression. Our calculations are relevant to the high pressure phase diagrams of helical magnets MnSi and Cu2OSeO3.

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A. M. Belemuk, S. M. Stishov. 2017-05-22. Monte Carlo modeling the phase diagram of magnets with the Dzyaloshinskii - Moriya interaction. https://doi.org/10.1016/j.ssc.2017.08.022

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