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arXiv · 2308.09707

Majorana zero modes in twisted transition metal dichalcogenides homobilayers

Xun-Jiang Luo·Wen-Xuan Qiu·Fengcheng Wu
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Abstract

Semiconductor moir\'e superlattices provide a highly tunable platform to study the interplay between electron correlation and band topology. For example, the generalized Kane-Mele-Hubbard model can be simulated by the topological moir\'e flat bands in twisted transition metal dichalcogenides homobilayers. For this system, we obtain the filling factor, twist angle, and electric field-dependent quantum phase diagrams with a plethora of phases, including the quantum spin Hall insulator, the in-plane antiferromagnetic state, the out-of-plane antiferromagnetic Chern insulator, the spin-polarized Chern insulator, the in-plane ferromagnetic state, and the 120$^\circ$ antiferromagnetic state. We predict that a gate-defined junction formed between the quantum spin Hall insulator phase with proximitized superconductivity and magnetic phases with in-plane magnetization (either ferromagnetic or antiferromagnetic) can realize one-dimensional topological superconductor with Majorana zero modes. Our proposal introduces semiconductor moir\'e homobilayers as an electrically tunable Majorana platform with no need of an external magnetic field.

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Xun-Jiang Luo, Wen-Xuan Qiu, Fengcheng Wu. 2023-08-18. Majorana zero modes in twisted transition metal dichalcogenides homobilayers. https://doi.org/10.1103/physrevb.109.l041103

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