Active Tuning of All-Dielectric Metasurfaces with Liquid Crystals

As optical metasurfaces are approaching the verge of practical applications, the possibility of dynamically controlling their optical properties becomes increasingly important. For plasmonic metasurfaces, considerable efforts have concentrated on tuning and switching their optical properties using liquid crystals (LCs) [1�3] utilizing either the strong temperature dependence of the LC optical anisotropy or their realignment in an external electric field. However, plasmonic metasurfaces suffer from strong dissipative losses of metals at optical frequencies. A solution to this problem is provided by all-dielectric metasurfaces consisting of two-dimensional arrangements of high-index dielectric nanoparticles with tailored optical properties, which allow for controlling lightwaves at the nanoscale with near-unity efficiency [4]. However, to date dynamic control of all-dielectric metasurfaces remains an open challenge and experimental realizations are still missing