Higher-order topological superconductivity in a topological metal 1T$^\prime$-MoTe$_2$

Sheng-Jie Huang; Kyungwha Park; Yi-Ting Hsu

doi:10.1038/s41535-024-00633-7

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arXiv · 2212.06197

Higher-order topological superconductivity in a topological metal 1T$^\prime$-MoTe$_2$

Sheng-Jie Huang·Kyungwha Park·Yi-Ting Hsu

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Abstract

One key challenge in the field of topological superconductivity (Tsc) has been the rareness of material realization. This is true not only for the first-order Tsc featuring Majorana surface modes, but also for the higher-order Tsc, which host Majorana hinge and corner modes. Here, we propose a four-step strategy that mathematically derives comprehensive guiding principles for the search and design for materials of general higher-order Tsc phases. Specifically, such recipes consist of conditions on the normal state and pairing symmetry that can lead to a given higher-order Tsc state. We demonstrate this strategy by obtaining recipes for achieving three-dimensional higher-order Tsc phases protected by the inversion symmetry. Following our recipe, we predict that the observed superconductivity in centrosymmetric MoTe$_2$ is a candidate for higher-order Tsc with corner modes. Our proposed strategy enables systematic materials search and design for higher-order Tsc, which can mobilize the experimental efforts and accelerate the material discovery for higher-order Tsc phases.

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Sheng-Jie Huang, Kyungwha Park, Yi-Ting Hsu. 2022-12-12. Higher-order topological superconductivity in a topological metal 1T$^\prime$-MoTe$_2$. https://doi.org/10.1038/s41535-024-00633-7

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