Correlated insulating states in a multi-layer TMD heterostructure with two moiré interfaces

In moiré superlattices of transitional metal dichalcogenides (TMD), the enhanced Coulomb interaction gives rise to rich correlated electronic states such as Mott insulators and generalized Wigner crystals. When two moiré superlattices of nearly identical periodicities are stacked together, interlayer hopping is expected, which adds a new degree of freedom for the study of correlated many-body physics. In this talk, we study angle-aligned monolayer WS₂/multilayer WSe₂/monolayer WS₂ heterostructure in a dual gate geometry and employ microwave impedance microscopy to probe the formation of insulating states. By applying a vertical electric field to tune the carrier distribution between the top and bottom moiré superlattices, we observe that certain insulating states disappear and reappear as a function of electric field, indicating possible competition and interaction between the two moiré superlattices.