Dynamically-tunable metastructures based on phase transition of vanadium dioxide

Tunable nanophotonic materials and devices are drawing intense attention with great promise for practical applications. In this work, we have experimentally demonstrated several dynamically-tunable metastructured devices based on phase transition of vanadium dioxide, which include dynamic plasmonic color generators, dynamically switchable polarizers, and dynamically tunable bowtie nanoantennas. First, we have fabricated periodic arrays of silver-nanodisks on a vanadium dioxide film to realize different colors, relying on the excitation of localized and propagating surface plasmons. Based on insulator-metal transition of vanadium dioxide, the plasmonic colors can be actively tuned by varying temperature. Second, we have demonstrated a system consisting of anisotropic plasmonic nanostructures with vanadium dioxide that exhibits distinct reflections subjected to different linearly polarized incidence at room temperature and in the heated state. Third, we have made the dynamically tunable bowtie nanoantennas integrated on a vanadium dioxide thin film. The investigations here can be applied in dynamic digital displays, optical data storage, and imaging sensors. References: 1) Adv. Opt. Mater.(2018) 6, 1700939; 2) Phys. Rev. Appl. (2018) 9, 034009; 3) Opt. Lett. (2019) 44, 2752.