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arXiv · 2406.19348

Superconductivity in twisted transition metal dichalcogenide homobilayers

Jihang Zhu·Yang-Zhi Chou·Ming Xie·Sankar Das Sarma
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Abstract

For the first time, robust superconductivity has been independently observed in twisted WSe$_2$ bilayers by two separate groups [Y. Xia et al., arXiv:2405.14784; Y. Guo et al., arXiv:2406.03418.]. In light of this, we explore the possibility of a universal superconducting pairing mechanism in twisted WSe$_2$ bilayers. Using a continuum band structure model and a phenomenological boson-mediated effective electron-electron attraction, we find that intervalley intralayer pairing predominates over interlayer pairing. Notably, despite different experimental conditions, both twisted WSe$_2$ samples exhibit a comparable effective attraction strength. This consistency suggests that the dominant pairing glue is likely independent of the twist angle and layer polarization, pointing to a universal underlying boson-induced pairing mechanism.

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Jihang Zhu, Yang-Zhi Chou, Ming Xie, Sankar Das Sarma. 2024-06-27. Superconductivity in twisted transition metal dichalcogenide homobilayers. https://doi.org/10.1103/physrevb.111.l060501

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