The interplay of field-tunable strongly correlated states in Γ and K moiré bands in a heterotrilayer device

In twisted transition metal dichalcogenide (TMD) heterobilayer systems the moiré bands that form the highest valence band generally arise from K-derived states. However, as more layers are added for naturally stacked TMDs the Γ valley becomes energetically relevant. Here, we optically probe the exciton-polarons in the presence of correlated states in a heterotrilayer 2H-bilayer WSe₂/monolayer MoSe₂ moiré heterostructure. We observe the formation of exciton-polarons where the direct exciton at ±K is dressed by holes residing in Γ derived moiré bands, evidenced by their distinctive hole-doping dependent dispersions. As the number of holes per moiré unit cell is tuned, abrupt changes of the attractive polarons reveal the formation of strongly correlated hole states within the Γ bands at both integer and intermediate fractional fillings. Upon application of a vertical electric field we change the ordering of Γ- and K-derived bands and transfer holes between Γ and K correlated states. Further, the WSe₂ attractive polarons dressed by the Γ and K correlated holes reveal contrasting polarisation properties under an applied magnetic field. The results are fully supported by density functional theory calculations which show highest Γ band projects onto a honeycomb lattice with inequivalent A and B sites, while the K band forms a triangular lattice. Our results reveal the potential of heterotrilayer TMDs for Hubbard model investigations for both honeycomb and triangular lattices within the same devices.