Thermoplasmonic-Controlled Optical Filters Based on the Combination of Chiral Liquid Crystals and Metasurfaces

A novel class of photonic filters is obtained by integrating a large-area optical plasmonic metasurface with a broadband cholesteric liquid crystal (CLC) Bragg reflector. By utilizing the photo-thermal characteristics of the optical plasmonic metasurface, the reflection properties of the CLC layer can be manipulated. The thermally induced variation of the CLC's pitch and the refractive index produces a reversible blue-redshift of the reflection band of about 80 nm. The synergistic interaction between these two effects enables the development of innovative optical color filters that integrate a light-tunable mirror and a controllable optical absorber.