Superconductivity near quarter and half filling of a strongly correlated triangular Hubbard band in twisted trilayer WSe2

Abstract

The triangular-lattice Hubbard model is one of the paradigmatic settings for studying correlated electronic systems with geometric frustration that can give rise to a variety of phases. Recently, twisted bilayer TMD systems have emerged as attractive experimental platforms for realising such a model in the moderate-correlation regime. Alternating twisted trilayer TMD systems are expected to realise stronger correlations than bilayer systems owing to their mirror symmetry. Here we report the discovery of superconductivity near quarter- and half-filling, together with various correlated phases, in alternating twisted trilayer WSe2 (TTWSe2). At half filling, a robust correlated insulating state persists over a broad range of displacement fields, signalling the strongly correlated regime. Upon doping, superconductivity emerges over an extended region of the phase diagram. Near quarter filling, another superconducting state appears flanked by correlated metals. Our results establish the TTWSe2 system as a compelling platform for studying strongly correlated triangular-lattice Hubbard physics.