Exciton Superposition across Moiré States in a Semiconducting Moiré Superlattice

Moiré superlattices of semiconducting transition metal dichalcogenides enable unprecedented spatial control of electron wavefunctions, leading to emerging quantum states. The breaking of translational symmetry further introduces a new degree of freedom: high symmetry moiré sites of energy minima behaving as spatially separated quantum dots. We demonstrate the superposition between two moiré sites by constructing a trilayer WSe₂/monolayer WS₂ moiré heterojunction. The two moiré sites in the first layer WSe₂ interfacing WS₂ allow the formation of two different interlayer excitons, with the hole residing in either moiré site of the first layer WSe₂ and the electron in the third layer WSe₂. An electric field can drive the hybridization of either of the interlayer excitons with the intralayer excitons in the third WSe₂ layer, realizing the continuous tuning of interlayer exciton hopping between two moiré sites and a superposition of the two interlayer excitons, distinctively different from the natural trilayer WSe₂.