In-Vivo Control of Excitons in TMDs

Excitons in heterostructures of atomically thin transition metal dichalcogenides (TMDs) have recently attracted attention as an appealing platform for optoelectronic and valleytronic devices, with a high degree of in-situ tunability provided through electrostatic gating. A major challenge in achieving such applications is the realization of dynamical control schemes, in which the properties of excitons are not pre-determined at the time of excitation but can also be modulated during their lifetime. Here, we demonstrate such "in-vivo" control of excitons by combining high-frequency electrical control with long-lived interlayer excitons in MoSe2/WSe2 heterobilayers. Through temporally-resolved photoluminescence measurements, we show in-vivo control of various exciton properties, including lifetime and resonance wavelength. These capabilities open the door for novel studies of exciton dynamics and for technological applications such as on-demand photon retrieval and the manipulation of information stored in TMD-based memory devices.