Terahertz light deflection in doped semiconductor slit arrays

We investigate the deflection of the terahertz light through the doped InSb subwavelength slit arrays. The deflection of light can be tailored by adjusting the doping concentrations of the InSb layers around the slits through the phase control. We have theoretically analyzed the properties of the InSb-air-InSb slits based on the plasmonic waveguide theory and the eigenvalue equations. Terahertz light deflectors with 30°, 45° and 60° deflection angles are systematically designed. By employing finite-difference time-domain (FDTD) simulation, the light deflection phenomenon is realized. The theoretically analyzed results demonstrate very good agreement with the simulated results.