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arXiv · 2303.11729

Hinge Majorana Flat Band in Type-II Dirac Semimetals

Yue Xie·Xianxin Wu·Zhong Fang·Zhijun Wang
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Abstract

Type-II Dirac semimetals exhibit a unique Fermi surface topology, which allows them to host novel topological superconductivity (TSC). We reveal a novel inter-orbital superconducting state, corresponding to the B1u and B2u pairings under the D4h point group. Intriguingly, we find that both first- and second-order TSC coexist in this novel state. It is induced by a dominant inter-orbital attraction and possesses surface helical Majorana cones and hinge Majorana flat bands, spanning the entire z-directed hinge Brillouin zone. Further investigation uncovers that these higher-order hinge modes are robust against the C4z symmetry-breaking perturbation.

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Yue Xie, Xianxin Wu, Zhong Fang, Zhijun Wang. 2023-03-21. Hinge Majorana Flat Band in Type-II Dirac Semimetals. https://doi.org/10.1007/s11433-024-2483-8

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