Tunable multispectral near-infrared absorption with a phase transition of VO nanoparticles hybridized with 1D photonic crystals.

We theoretically demonstrate a switchable multichannel near-infrared absorber in a composite structure based on vanadium dioxide nanoparticles embedded between two and one-dimensional photonic crystal mirrors. A switching of absorption behavior is induced through the reversible semiconductor-to-metal phase transition of vanadium dioxide nanoparticles via its temperature-dependent permittivity-thermo-optical effect. This behavior leads to a multi-wavelength reconfigurable optical response of the proposed structure from poorly absorbing to highly absorbing. For example, there is the possibility of enhancement of absorption from ∼0.14 to ∼0.75 at normal incidence of light by increasing the temperature beyond the critical value of ∼341 K when the vanadium dioxide nanoparticles transform from a semiconducting state into a metallic one. These properties make the considered structure applicable for use in multiband absorbers, light detectors, and optical switching devices.