Optical resonators are a powerful platform to control the spontaneous emission dynamics of excitons in solidstate nanostructures.We study a MoSe_(2)-WSe_(2)heterostructure that is integrated in a cryogenic open optica...Optical resonators are a powerful platform to control the spontaneous emission dynamics of excitons in solidstate nanostructures.We study a MoSe_(2)-WSe_(2)heterostructure that is integrated in a cryogenic open optical microcavity to gain insights into fundamental optical properties of the emergent interlayer excitons.First,we utilize a low-quality-factor planar open cavity and investigate the modification of the excitonic lifetime as on-and offresonance conditions are met with consecutive longitudinal modes.Time-resolved photoluminescence measurements revealed a periodic tuning of the interlayer exciton lifetime by 220 ps,which allows us to extract a 0.5 ns free-space radiative lifetime and a quantum efficiency as high as 81.4%±1.4%.We subsequently engineer the local density of optical states by spatially confined and spectrally tunable Tamm-plasmon resonances.The dramatic redistribution of the local optical modes allows us to encounter a significant inhibition of the excitonic spontaneous emission rate by a factor of 3.2.Our open cavity is able to tune the cavity resonances accurately to the emitters to have a robust in situ control of the light-matter coupling.Such a powerful characterization approach can be universally applied to tune the exciton dynamics and measure the quantum efficiencies of more complex van der Waals heterostructures and devices.展开更多
文摘Optical resonators are a powerful platform to control the spontaneous emission dynamics of excitons in solidstate nanostructures.We study a MoSe_(2)-WSe_(2)heterostructure that is integrated in a cryogenic open optical microcavity to gain insights into fundamental optical properties of the emergent interlayer excitons.First,we utilize a low-quality-factor planar open cavity and investigate the modification of the excitonic lifetime as on-and offresonance conditions are met with consecutive longitudinal modes.Time-resolved photoluminescence measurements revealed a periodic tuning of the interlayer exciton lifetime by 220 ps,which allows us to extract a 0.5 ns free-space radiative lifetime and a quantum efficiency as high as 81.4%±1.4%.We subsequently engineer the local density of optical states by spatially confined and spectrally tunable Tamm-plasmon resonances.The dramatic redistribution of the local optical modes allows us to encounter a significant inhibition of the excitonic spontaneous emission rate by a factor of 3.2.Our open cavity is able to tune the cavity resonances accurately to the emitters to have a robust in situ control of the light-matter coupling.Such a powerful characterization approach can be universally applied to tune the exciton dynamics and measure the quantum efficiencies of more complex van der Waals heterostructures and devices.
