Dataset: Designing Flat Bands, Localized and Itinerant States in TaS2 Trilayer Heterostructures

Abstract Stacking and twisting van der Waals materials provide a powerful tool to engineer quantum matter. For instance, monolayer 1T-TaS2 is Mott insulating, whereas 1H-TaS2 is metallic and superconducting; their T/H bilayer have been extensively investigated in the context of heavy fermions and unconventional superconductivity, which are expected phases from localized spins (1T) coexisting with itinerant electrons (1H). However, significant charge transfer quenches the 1T Mottness and renders the above scenario elusive. Here we propose a T/T/H trilayer heterostructure by combining a T/T bilayer – a band insulator with flat dispersion – with a 1H layer. After charge redistribution, the T/T bilayer retains localized spins, whereas the 1H layer remains metallic with weak spin polarization. Varying the T/T stacking configuration tunes the flat-band filling, enabling a possible crossover from a doped-Mott regime to a Kondo-like hybridized state. The T/T/H trilayer provides therefore a rich novel heterostructure platform to study strong correlation phenomena and unconventional superconductivity.