Superconductivity in twisted bilayer WSe$_2$
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 (tWSe) 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.
Cite
@article{arxiv.2406.03418,
title = {Superconductivity in twisted bilayer WSe$_2$},
author = {Yinjie Guo and Jordan Pack and Joshua Swann and Luke Holtzman and Matthew Cothrine and Kenji Watanabe and Takashi Taniguchi and David Mandrus and Katayun Barmak and James Hone and Andrew J. Millis and Abhay N. Pasupathy and Cory R. Dean},
journal= {arXiv preprint arXiv:2406.03418},
year = {2025}
}