Nonlocal Interactions in Moiré Hubbard Systems

Mapping twist-tuned multiband topology in bilayer WSe 2

“…Our work motivates further studies to confirm the specific spin/ valley symmetry breaking of the odd-integer gaps, as well as transport studies to confirm whether quantum spin Hall insulating states are realized at even integers, including a potential double quantum spin Hall insulator at n ¼ À4 (29). More generally, this work opens a platform for studying tunable topological bands in the limit of larger moiré wavelengths where interacting phases such as fractional Chern insulators may be more readily stabilized (46,47).…”

Chiral superconductivity with enhanced quantized Hall responses in moiré transition metal dichalcogenides

“…In experiment, the filling can be adjusted, and Van Hove filling can be reached, by tuning the gate voltage, which we model here by varying the chemical potential μ between 1/4 and 1/2 filling. The interaction parameters U, V n also depend on the twist angle, and on the dielectric environment so that the strength and range of interactions can be controlled 43 . First-principles calculations show that the extended interactions V n are sizable in effective models for hetero-bilayer TMDs 34 .…”

Moiré alchemy: artificial atoms, Wigner molecules, and emergent Kagome lattice

“…To date, much theoretical analysis has relied on an effective Hubbard model description of interacting electrons in the lowest few moiré bands [4][5][6][7]. This approach successfully explains and predicts many observed phenomena such as the emergence of Mott insulators at n = 1 [8,9], incompressible Wigner crystals at fractional fillings n < 1 [8,[10][11][12][13][14][15][16][17] and charge transfer between distinct species of moiré atoms at n > 1 [5,[18][19][20][21] (n is the number of doped electrons or holes per moiré unit cell).…”