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arXiv · 2206.01304

Engineering chiral topological superconductivity in twisted Ising superconductors

Xiaodong Hu·Ying Ran
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Abstract

Van der Waals materials like NbSe$_2$ or TaS$_2$ have demonstrated Ising superconductivity down to atomically thin layers. Due to the spin-orbit coupling, these superconductors have the in-plane upper critical magnetic field far beyond the Pauli limit. We theoretically demonstrate that, twisted bilayer Ising superconductors separated by a ferromagnetic buffer layer can naturally host chiral topological superconductivity with Chern numbers, which can be realized in heterostructures like $\mathrm{NbSe_2/CrCl_3/NbSe_2}$. Under appropriate experimental conditions the topological superconducting gap can reach $>0.1$ meV, leading to readily observable signatures such as the quantized thermal Hall transport at low temperatures.

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Xiaodong Hu, Ying Ran. 2022-06-02. Engineering chiral topological superconductivity in twisted Ising superconductors. https://doi.org/10.1103/physrevb.106.125136

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