Reconfigurable asymmetrical broadband mid-infrared light filter design by materials informatics

A reconfigurable asymmetrical broadband mid-infrared light filter utilizing a vanadium dioxide (VO2) triangular grating structure is designed by materials informatics. The design applies the unique phase-transition characteristics of VO2 to facilitate asymmetrical light transmission, enhancing forward transmission via surface plasmon polaritons when VO2 is metallic state at high temperatures. At lower temperatures, as VO2 transitions to a dielectric state, no free electrons are available for excitation, resulting in a more symmetric transmission. The operational bandwidth or wavelength of the filter can be adjusted through geometric parameters of the triangular structures.