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arXiv · 2209.11724

Superconductivity in the twisted bilayer transition metal dichalcogenide WSe${}_2$ : a quantum cluster study

Mathieu Bélanger·Jérôme Fournier·David Sénéchal
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Abstract

The observation of flat energy bands in transition metal dichalcogenide bilayers such as twisted WSe${}_2$ makes those materials interesting prospects for reproducing the behavior observed in graphene-based systems. We use an effective Hubbard model providing a description of twisted WSe${}_2$ to explore the presence of superconductivity, which was previously reported in experiments. Using both the variational cluster approximation and cluster dynamical mean-field theory, we predict the existence of chiral supercondictivity of type $d\pm id$ that can be tuned by the twist angle and by the application of a perpendicular displacement field, in both electron- and hole-doped systems.

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Mathieu Bélanger, Jérôme Fournier, David Sénéchal. 2022-09-23. Superconductivity in the twisted bilayer transition metal dichalcogenide WSe${}_2$ : a quantum cluster study. https://doi.org/10.1103/physrevb.106.235135

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