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arXiv · 1802.07172

Spin-1/2 anisotropic Heisenberg antiferromagnet with Dzyaloshinskii-Moriya interaction via mean-field approximation

Walter E. F. Parente·J. T. M. Pacobahyba·Minos A. Neto·Ijanílio G. Araújo·J. A. Plascak
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Abstract

The spin-1/2 anisotropic Heisenberg model with antiferromagnetic exchange interactions in the presence of a external magnetic field and a Dzyaloshinskii-Moriya interaction is studied by employing the usual mean-field approximation. The magnetic properties are obtained and it is shown that only second-order phase transitions take place for any values of the theoretical Hamiltonian parameters. Contrary to previous results from effective field theory, no anomalies have been observed at low temperatures. However, some re-entrancies still persist in some region of the phase diagram.

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Walter E. F. Parente, J. T. M. Pacobahyba, Minos A. Neto, Ijanílio G. Araújo, J. A. Plascak. 2018-02-20. Spin-1/2 anisotropic Heisenberg antiferromagnet with Dzyaloshinskii-Moriya interaction via mean-field approximation. https://doi.org/10.1016/j.jmmm.2018.04.054

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