Superconductivity in twisted bilayer WSe$_2$

Yinjie Guo; Jordan Pack; Joshua Swann; Luke Holtzman; Matthew Cothrine; Kenji Watanabe; Takashi Taniguchi; David Mandrus; Katayun Barmak; James Hone; Andrew J. Millis; Abhay N. Pasupathy; Cory R. Dean

doi:10.1038/s41586-024-08381-1

arXiv · 2406.03418

Superconductivity in twisted bilayer WSe$_2$

Yinjie Guo·Jordan Pack·Joshua Swann·Luke Holtzman·Matthew Cothrine·Kenji Watanabe·Takashi Taniguchi·David Mandrus·Katayun Barmak·James Hone·Andrew J. Millis·Abhay N. Pasupathy·Cory R. Dean

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Abstract

The discovery of superconductivity in twisted bilayer and twisted trilayer graphene has generated tremendous interest. The key feature of these systems is an interplay between interlayer coupling and a moir\'e superlattice that gives rise to low-energy flat bands with strong correlations. Flat bands can also be induced by moir\'e patterns in lattice-mismatched and or twisted heterostructures of other two-dimensional materials such as transition metal dichalcogenides (TMDs). Although a wide range of correlated phenomenon have indeed been observed in the moir\'e TMDs, robust demonstration of superconductivity has remained absent. Here we report superconductivity in 5 degree twisted bilayer WSe$_2$ (tWSe$_2$) with a maximum critical temperature of 426 mK. The superconducting state appears in a limited region of displacement field and density that is adjacent to a metallic state with Fermi surface reconstruction believed to arise from antiferromagnetic order. A sharp boundary is observed between the superconducting and magnetic phases at low temperature, reminiscent of spin-fluctuation mediated superconductivity. Our results establish that moir\'e flat-band superconductivity extends beyond graphene structures. Material properties that are absent in graphene but intrinsic among the TMDs such as a native band gap, large spin-orbit coupling, spin-valley locking, and magnetism offer the possibility to access a broader superconducting parameter space than graphene-only structures.

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Yinjie Guo, Jordan Pack, Joshua Swann, Luke Holtzman, Matthew Cothrine, Kenji Watanabe, Takashi Taniguchi, David Mandrus, Katayun Barmak, James Hone, Andrew J. Millis, Abhay N. Pasupathy, Cory R. Dean. 2024-06-05. Superconductivity in twisted bilayer WSe$_2$. https://doi.org/10.1038/s41586-024-08381-1

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