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arXiv · 2307.16538

Phase diagram of a ferromagnetic semiconductor. The origin of superparamagnetism

N. A. Bogoslovskiy·P. V. Petrov·N. S. Averkiev
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Abstract

We study the theoretical model of a ferromagnetic semiconductor as a system of randomly distributed Ising spins with a long-range exchange interaction. Using the density-of-states approach, we analytically obtain the magnetic susceptibility and heat capacity over a wide range of temperatures and magnetic fields. It is shown that the finite system of spins in magnetic field less than a certain critical field is in a superparamagnetic state due to thermodynamic fluctuations. The complex phase structure of a ferromagnetic semiconductor is discussed.

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N. A. Bogoslovskiy, P. V. Petrov, N. S. Averkiev. 2023-07-31. Phase diagram of a ferromagnetic semiconductor. The origin of superparamagnetism. https://doi.org/10.1103/physrevb.109.024436

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