High Chern number van der Waals magnetic topological multilayers MnBi2Te4/hBN

Chern insulators are two-dimensional magnetic topological materials that conduct electricity along their edges via the one-dimensional chiral modes. The number of these modes is a topological invariant called the first Chern number C that defines the quantized Hall conductance as S-xy = Ce-2/h. Increasing C is pivotal for the realization of low-power-consumption topological electronics, but there has been no clear-cut solution to this problem so far, with the majority of existing Chern insulators showing C = 1. Here, by using state-of-the-art theoretical methods, we propose an efficient approach for the realization of the high-C state in MnBi2Te4/hBN van der Waals multilayer heterostructures. We show that a stack of n MnBi2Te4 films with C = 1 intercalated by hBN monolayers gives rise to a high Chern number state with C = n, characterized by n chiral edge modes. This state can be achieved both under the external magnetic field and without it, both cases leading to the quantized Hall conductance S-xy = Ce-2/h. Our results, therefore, pave the way to practical high-C quantized Hall systems.

Automated summary

Chern insulators are two-dimensional magnetic topological materials that conduct electricity along their edges via one-dimensional chiral modes. We propose an efficient approach for achieving high Chern number states in MnBi2Te4/hBN van der Waals multilayer heterostructures. Our results show that a stack of n MnBi2Te4 films intercalated by hBN monolayers can give rise to a high Chern number state with n chiral edge modes. This state can be achieved both with and without an external magnetic field, resulting in quantized Hall conductance. Our findings pave the way for practical high Chern number quantized Hall systems.