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arXiv · 2105.04523

Model studies of topological phase transitions in materials with two types of magnetic atoms

Zhuoran He·Gang Xu
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Abstract

We study the topological phase transitions induced by Coulomb engineering in three triangular-lattice Hubbard models $AB_2$, $AC_3$ and $B_2C_3$, each of which consists of two types of magnetic atoms with opposite magnetic moments. The energy bands are calculated using the Schwinger boson method. We find that a topological phase transition can be triggered by the second-order (three-site) virtual processes between the two types of magnetic atoms, the strengths of which are controlled by the on-site Coulomb interaction $U$. This new class of topological phase transitions have been rarely studied and may be realized in a variety of real magnetic materials.

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Zhuoran He, Gang Xu. 2021-05-10. Model studies of topological phase transitions in materials with two types of magnetic atoms. https://doi.org/10.1103/physrevb.104.235108

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