Atomically thin semiconductors exhibit tunable exciton resonances that can be harnessed for dynamic manipulation of visible light in ultra-compact metadevices.However,the rapid nonradiative decay and dephasing of exci...Atomically thin semiconductors exhibit tunable exciton resonances that can be harnessed for dynamic manipulation of visible light in ultra-compact metadevices.However,the rapid nonradiative decay and dephasing of excitons at room temperature limit current active excitonic metasurfaces to a few-percent efficiencies.Here,we leverage the combined merits of pristine 2D heterostructures and non-local dielectric metasurfaces to enhance the excitonic lightmatter interaction,achieving strong and electrically tunable exciton-photon coupling at ambient conditions in a hybrid-2D excitonic metasurface.Using this,we realize a free-space optical modulator and experimentally demonstrate 9.9 dB of reflectance modulation.The electro-optic response,characterized by a continuous transition from strong to weak coupling,is mediated by gating-induced variations in the free carrier concentration,altering the exciton’s nonradiative decay rate.These results highlight how hybrid-2D excitonic metasurfaces offer novel opportunities to realize nanophotonic devices for active wavefront manipulation and optical communication.展开更多
基金funded by a Vidi grant(VI.Vidi.203.027)from the Dutch National Science Foundation(NWO).
文摘Atomically thin semiconductors exhibit tunable exciton resonances that can be harnessed for dynamic manipulation of visible light in ultra-compact metadevices.However,the rapid nonradiative decay and dephasing of excitons at room temperature limit current active excitonic metasurfaces to a few-percent efficiencies.Here,we leverage the combined merits of pristine 2D heterostructures and non-local dielectric metasurfaces to enhance the excitonic lightmatter interaction,achieving strong and electrically tunable exciton-photon coupling at ambient conditions in a hybrid-2D excitonic metasurface.Using this,we realize a free-space optical modulator and experimentally demonstrate 9.9 dB of reflectance modulation.The electro-optic response,characterized by a continuous transition from strong to weak coupling,is mediated by gating-induced variations in the free carrier concentration,altering the exciton’s nonradiative decay rate.These results highlight how hybrid-2D excitonic metasurfaces offer novel opportunities to realize nanophotonic devices for active wavefront manipulation and optical communication.
