Addressable Metasurfaces by Electrically Driven Transparent Conducting Oxide Micro-Heaters

Recently, metasurfaces have attracted much interest because of their exceptional light-scattering properties. The geometrical parameters and material properties dictate the optical response observed in metasurfaces. Therefore, the fixed geometry of the metasurfaces has been an obstacle to the tunability of their scattering properties. The modulation in refractive index by altering the material's temperature, or thermo-optical effect, is recently exploited to change the optical response of the metasurfaces [1,2]. This work demonstrates the programmable tuning of dielectric hole-array metasurfaces made of hydrogenated amorphous silicon by electrically driven transparent micro-heaters (Figure 1a,b). This approach overcomes the shortcomings of the previous works, namely the switching speed and programmability.