Moiré-Orbital-Resolved Excitonic Mott Insulating States and Their Optical and Electric Control in van der Waals Heterostructures

Moiré potential formed in van der Waals heterostructures is predicted to feature multiple local minima functioning as orbital degree of freedom, which is an important ingredient for understanding intriguing strong correlation phenomena. However, an experimental demonstration of this moiré-orbital enabled quantum state engineering is still unexplored. Here, we report clear evidence of moiré-orbital resolved excitonic Mott insulating states in multiannealing H-type WSe_{2}/WS_{2} heterobilayers and demonstrate their application in generating spatially ordered excitonic quantum phases. This moiré orbital is evidenced by interlayer exciton emissions with an energy separation of ∼65 meV and further supported by our multiple field-dependent characterizations. Remarkably, the moiré orbital allows a sequential formation of correlated Mott insulating states, with the extracted onsite Hubbard interaction reaching ∼30 meV. A combined optical and electric doping allows control of strongly correlated quantum phases with various spatially ordered fermionic-bosonic orbital components.