Bohn, JustusBucher, TobiasChong, Katie E.Komar, AndreiChoi, Duk-YongNeshev, DragomirKivshar, YuriPertsch, ThomasStaude, Isabelle2021-10-181530-6984http://hdl.handle.net/1885/250974Mie-resonant dielectric metasurfaces offer comprehensive opportunities for the manipulation of light fields with high efficiency. Additionally, various strategies for the dynamic tuning of the optical response of such metasurfaces were demonstrated, making them important candidates for reconfigurable optical devices. However, dynamic control of the light-emission properties of active Mie-resonant dielectric metasurfaces by an external control parameter has not been demonstrated so far. Here, we experimentally demonstrate the dynamic tuning of spontaneous emission from a Mie-resonant dielectric metasurface that is situated on a fluorescent substrate and embedded into a liquid crystal cell. By switching the liquid crystal from the nematic state to the isotropic state via control of the cell temperature, we induce a shift of the spectral position of the metasurface resonances. This results in a change of the local photonic density of states, which, in turn, governs the enhancement of spontaneous emission from the substrate. Specifically, we observe spectral tuning of both the electric and magnetic dipole resonances, resulting in a 2-fold increase of the emission intensity at λ ≈ 900 nm. Our results demonstrate a viable strategy to realize flat tunable light sources based on dielectric metasurfaces.This research was partially funded by the German Ministry of Education and Research (BMBF) under the project identifier 13N14147; responsibility for the content of this work resides with the authors. Financial support by the Thuringian State Government within its ProExcellence initiative (ACP2020) and by the German Research Foundation (STA 1426/2-1) is also gratefully acknowledged. The authors furthermore acknowledge the support of the Australian Research Council and their participation in the Erasmus Mundus NANOPHI project (contract no. 2013 5659/002-001). This project was also supported by the German Academic Exchange Service (DAAD) through the funds of the German Ministry of Education and Research (BMBF). A.K. and D.N.N. acknowledge the support of the Universities Australia−Germany Joint Research Cooperation Scheme. Y.S.K. acknowledges support from the Alexander von Humboldt Foundation. This research is supported by an Australian Government Research Training Program (RTP) Scholarship.application/pdfen-AU© 2018 American Chemical SocietyAll-dielectric nanophotonicsdielectric nanoantennasMie resonancesemission enhancementtunable metasurfacesactive metasurfacesliquid crystals201810.1021/acs.nanolett.8b004752020-11-23