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arXiv · 2001.02796

Moir\'e magnets

Kasra Hejazi·Zhu-Xi Luo·Leon Balents
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Abstract

We introduce a general framework to study moir\'e structures of two-dimensional Van der Waals magnets using continuum field theory. The formalism eliminates quasiperiodicity and allows a full understanding of magnetic structures and their excitations. In particular, we analyze in detail twisted bilayers of N\'eel antiferromagnets on the honeycomb lattice. A rich phase diagram with non-collinear twisted phases is obtained, and spin waves are further calculated. Direct extensions to zig-zag antiferromagnets and ferromagnets are also presented. We anticipate the results and formalism presented to lead to a broad range of applications to both fundamental research and experiments.

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Kasra Hejazi, Zhu-Xi Luo, Leon Balents. 2020-01-09. Moir\'e magnets. https://arxiv.org/abs/2001.02796

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