Higher-order topological superconductivity in monolayer WTe$_2$ from repulsive interactions

Ammar Jahin; Yuxuan Wang

doi:10.1103/physrevb.108.014509

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arXiv · 2303.11345

Higher-order topological superconductivity in monolayer WTe$_2$ from repulsive interactions

Ammar Jahin·Yuxuan Wang

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Abstract

Superconductivity has been experimentally observed in monolayer WTe2, which in-plane field measurements suggested are of spin-triplet nature. Furthermore, it has been proposed that with a $p$-wave pairing, the material is a second-order topological superconductor with a pair of Majorana zero modes at the corners of a finite sample. We show that for a repulsive on-site interaction and sizable Fermi surfaces, the desired p-wave state arises naturally due to the Kohn-Luttinger mechanism, and indeed a finite superconducting sample hosts corner Majorana zero modes. We study the behavior of the critical temperature in response to external in-plane magnetic fields. We find an enhancement to the critical temperature that depends on the direction of the magnetic field, which can be directly verified experimentally.

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Ammar Jahin, Yuxuan Wang. 2023-03-20. Higher-order topological superconductivity in monolayer WTe$_2$ from repulsive interactions. https://doi.org/10.1103/physrevb.108.014509

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