Ferromagnetic Heisenberg model with the Dzyaloshinskii-Moriya interaction

Autor: E. Albayrak
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Condensed Matter Physics, Vol 25, Iss 3, p 33701 (2022)
Druh dokumentu: article
ISSN: 1607-324X
2224-9079
DOI: 10.5488/CMP.25.33701
Popis: The spin-1/2 Heisenberg model is formulated in terms of a mean-field approximation (MFA) by using the matrix forms of spin operators Ŝ_x, Ŝ_y and Ŝ_z in three-dimensions. The considered Hamiltonian consists of bilinear exchange interaction parameters (J_x, J_y, J_z), Dzyaloshinskii-Moriya interactions (Δ_x, Δ_y, Δ_z) and external magnetic field components (H_x, H_y, H_z). The magnetization and its components are obtained in the MFA with the general anisotropic case with J_x ≠ J_y ≠ J_z for various values of coordination numbers q. Then, the thermal variations of magnetizations are investigated in detail to obtain the phase diagrams of the model for the isotropic case with J_x = J_y = J_z > 0. It is found that the model exhibits ferromagnetic, paramagnetic, random phase regions and an extra ferromagnetic phase at which the components of magnetizations present branching.
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