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Noncollinear phases in moire magnets.

ABSTRACT: We introduce a general framework to study moiré 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 Néel antiferromagnets on the honeycomb lattice. A rich phase diagram with noncollinear twisted phases is obtained, and spin waves are further calculated. Direct extensions to zigzag antiferromagnets and ferromagnets are also presented. We anticipate the results and formalism demonstrated to lead to a broad range of applications to both fundamental research and experiments.

SUBMITTER: Hejazi K

PROVIDER: S-EPMC7245139 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Noncollinear phases in moiré magnets.

Hejazi Kasra K Luo Zhu-Xi ZX Balents Leon L

Proceedings of the National Academy of Sciences of the United States of America 20200504 20

We introduce a general framework to study moiré 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 Néel antiferromagnets on the honeycomb lattice. A rich phase diagram with noncollinear twisted phases is obtained, and spin waves are further calculated. Direct extensions to zigzag antiferromag ...[more]

PMID: 32366657

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