Multifunctional metasurface based bandstop and bandpass filters for terahertz radiation

A multifunctional metasurface using all dielectric structure comprising an array of InAs square pillar over the InSb substrate has been realized. The considered metasurface shows zero reflection and close to unity transmission at single as well as dual frequency in the terahertz spectral regime with the application of magnetic field. This metasurface also exhibits switching action from bandpass to bandstop over the designed frequency regime with the exposure of varying magnetic field from 0 to 0.2 T. The tunability in the maximum transmittance frequency is achieved by the variation in temperature of Insb substrate which acts as another control modality showing a blue shift from 2.37 THz to 2.65 THz at an average tuning rate of 0.028 THz K-1. The proposed all dielectric metasurface is designed to function as a switch, bandstop and bandpass filter for the terahertz spectral regime thus acting as multifunctional metasurface, thereby reduces inventory cost as well as additional peripheral utility devices.