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arXiv · 2203.04505

Ferromagnetism in layered metallic Fe1/4TaS2 in the presence of conventional and Dirac carriers

Jin-Hua Wang·Ya-Min Quan·Da-Yong Liu·Liang-Jian Zou
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Abstract

In this paper we present the microscopic origin of the ferromagnetism of Fe0.25TaS2 and its finite-temperature magnetic properties. We first obtain the band structures of Fe0.25TaS2 by the first-principles calculations and find that both conventional and Dirac carriers coexist in metallic Fe0.25TaS2. Accordingly, considering the spin-orbit coupling of Fe 3d ion, we derive an effective RKKY-type Hamiltonian between Fe spins in the presence of both the conventional parabolic-dispersion and the Dirac linear-dispersion carriers, which contains a Heisenberg-like, an Ising-like and an XY-like term. In addition, we obtain the ferromagnetic Curie temperature Tc by using the cluster self-consistent field method. Our results could address not only the high ferromagnetic Curie temperature, but also the large magnetic anisotropy in FexTaS2.

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Jin-Hua Wang, Ya-Min Quan, Da-Yong Liu, Liang-Jian Zou. 2022-03-09. Ferromagnetism in layered metallic Fe1/4TaS2 in the presence of conventional and Dirac carriers. https://doi.org/10.1088/0256-307x%2F37%2F1%2F017101

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