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arXiv · 1511.08381

Spin textures and spin-wave excitations in doped Dirac-Weyl semimetals

Yasufumi Araki·Kentaro Nomura
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Abstract

We study correlations and magnetic textures of localized spins, doped in three-dimensional Dirac semimetals. An effective field theory for magnetic moments is constructed by integrating out the fermionic degrees of freedom. The spin correlation shows a strong anisotropy, originating from spin-momentum locking of Dirac electrons, in addition to the conventional Heisenberg-like ferromagnetic correlation. The anisotropic spin correlation allows topologically nontrivial magnetic excitation textures such as a transient hedgehog state, as well as the ferromagnetic ground state. The spin-wave dispersion in ferromagnetic Weyl semimetal also becomes anisotropic, being less dispersed perpendicular to the magnetization.

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Yasufumi Araki, Kentaro Nomura. 2015-11-26. Spin textures and spin-wave excitations in doped Dirac-Weyl semimetals. https://doi.org/10.1103/physrevb.93.094438

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