Dzyaloshinskii-Moriya interaction in absence of spin-orbit coupling

Ramon Cardias; Anders Bergman; Attila Szilva; Yaroslav O. Kvashnin; Jonas Fransson; Angela B. Klautau; Olle Eriksson; Lars Nordström

arXiv · 2003.04680

Dzyaloshinskii-Moriya interaction in absence of spin-orbit coupling

Ramon Cardias·Anders Bergman·Attila Szilva·Yaroslav O. Kvashnin·Jonas Fransson·Angela B. Klautau·Olle Eriksson·Lars Nordström

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Abstract

In contrast to conventional assumptions, we show that the Dzyaloshinskii-Moriya interaction can be of non-relativistic origin, in particular in materials with a non-collinear magnetic configuration, where non-relativistic contributions can dominate over spin-orbit effects. The weak antiferromagnetic phase of Mn$_{3}$Sn is used to illustrate these findings. Using electronic structure theory as a conceptual platform, all relevant exchange interactions are derived for a general, non-collinear magnetic state. It is demonstrated that non-collinearity influences all three types of exchange interaction and that physically distinct mechanisms, which connect to electron- and spin-density and currents, may be used as a general way to analyze and understand magnetic interactions of the solid state.

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Ramon Cardias, Anders Bergman, Attila Szilva, Yaroslav O. Kvashnin, Jonas Fransson, Angela B. Klautau, Olle Eriksson, Lars Nordström. 2020-03-17. Dzyaloshinskii-Moriya interaction in absence of spin-orbit coupling. https://arxiv.org/abs/2003.04680

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