Quantum dynamics of electrostatically confined exciton

The ferroelectric moiré domains in twisted hexagonal boron nitride(t-bBN) structures provide a versatile platform for electrostatically confining excitonic states. For instance, the in-plane electric field at domain walls creates a potential trap, enabling the quantum confinement of excitons. Here, we utilize two-dimensional coherent spectroscopy (2DCS) to investigate the quantum dynamics of excitons in transition metal dichalcogenide monolayer and bilayers adjacent to a t-hBN substrate. We observe two distinct resonances corresponding to localized and delocalized excitons, respectively. Using 2DCS, we directly measure the dephasing times of these excitons and demonstrate the coupling between them.