English

Origins of anisotropic transport in electrically-switchable antiferromagnet $\mathrm{Fe_1/3NbS_2}$

Materials Science 2021-07-07 v1

Abstract

Recent experiments on the antiferromagnetic intercalated transition metal dichalcogenide Fe1/3NbS2\mathrm{Fe_{1/3}NbS_2} have demonstrated reversible resistivity switching by application of orthogonal current pulses below its magnetic ordering temperature, making Fe1/3NbS2\mathrm{Fe_{1/3}NbS_2} promising for spintronics applications. Here, we perform density functional theory calculations with Hubbard U corrections of the magnetic order, electronic structure, and transport properties of crystalline Fe1/3NbS2\mathrm{Fe_{1/3}NbS_2}, clarifying the origin of the different resistance states. The two experimentally proposed antiferromagnetic ground states, corresponding to in-plane stripe and zigzag ordering, are computed to be nearly degenerate. In-plane cross sections of the calculated Fermi surfaces are anisotropic for both magnetic orderings, with the degree of anisotropy sensitive to the Hubbard U value. The in-plane resistance, computed within the Kubo linear response formalism using a constant relaxation time approximation, is also anisotropic, supporting a hypothesis that the current-induced resistance changes are due to a repopulating of AFM domains. Our calculations indicate that the transport anisotropy of Fe1/3NbS2\mathrm{Fe_{1/3}NbS_2} in the zigzag phase is reduced relative to stripe, consistent with the relative magnitudes of resistivity changes in experiment. Finally, our calculations reveal the likely directionality of the current-domain response, specifically, which domains are energetically stabilized for a given current direction.

Keywords

Cite

@article{arxiv.2104.07591,
  title  = {Origins of anisotropic transport in electrically-switchable antiferromagnet $\mathrm{Fe_1/3NbS_2}$},
  author = {Sophie F. Weber and Jeffrey B. Neaton},
  journal= {arXiv preprint arXiv:2104.07591},
  year   = {2021}
}