Room-temperature efficient and tunable interlayer exciton emissions in WS2/WSe2 heterobilayers at high generation rates

Transition metal dichalcogenide (TMDC) heterobilayers (HBs) have been intensively investigated lately because they offer novel platforms for the exploration of interlayer excitons (IXs). However, the potentials of IXs in TMDC HBs have not been fully studied as efficient and tunable emitters for both photoluminescence (PL) and electroluminescence (EL) at room temperature (RT). Also, the efficiencies of the PL and EL of IXs have not been carefully quantified. In this work, we demonstrate that IX in WS2/WSe2 HBs could serve as promising emitters at high generation rates due to its immunity to efficiency roll-off. Furthermore, by applying gate voltages to balance the electron and hole concentrations and to reinforce the built-in electric fields, high PL quantum yield (QY) and EL external quantum efficiency (EQE) of similar to 0.48% and similar to 0.11% were achieved at RT, respectively, with generation rates exceeding 10(21 )cm(-2)<middle dot>s(-1), which confirms the capabilities of IXs as efficient NIR light emitters by surpassing most of the intralayer emissions from TMDCs. (c) 2024 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.