Adaptive and Reconfigurable Optical Metasurfaces

Metasurface light manipulation is traditionally achieved through the physical patterning of periodically arranged sub-wavelength unit cells via electron beam lithography. Subsequent etching of these patterned devices has been able to realize surfaces with properties such as near perfect absorption and subwavelength focusing. However, despite these significant achievements, the nano-patterning of most unit cell materials produces static electromagnetic properties that limits the theoretical bounds of performance and functionality. Phase-change materials (PCMs) provide an opportunity to overcome this limitation since they can be transitioned between two material phases with distinct optical properties. Herein, we investigate the use of antimony-trisulfide $(\text{Sb}_{2}\mathrm{S}_{3})$ , a new class of low-loss optical chalcogenide PCMs, for the development of reconfigurable metasurfaces in the infrared (IR). We also investigate vanadium oxide (VOx) metasurfaces for tunable and adaptive controlled thermal IR emissions. The development of $\text{Sb}_{2}\mathrm{S}_{3}$ and VOx based reconfigurable metasurfaces in the IR offer a promising path towards achieving new functionalities and higher overall efficiencies than what are currently achieved today.