Light-Controlled Polarization of MM-Waves with Photo-Excited Gratings in a Resonant Semiconductor Slab

Abstract

We investigated photoconductive gratings in the resonant semiconductor layers as light-controlled polarizers for the millimeter (MM) waves. We compared the effects of strip-like, wire-like, and fin-like gratings excited by the red light and the IR radiation in Silicon wafers, respectively. The fin-like gratings are shown to be the preferred structures that can operate at the limited light intensity. The light-sensitive shift of maxima of transmitted power and polarizing efficiency towards the lower frequency band is observed. The effect makes photoconductive gratings and similar patterns potentially suitable for the design of light-controlled frequency-tuning and frequency-modulating components of resonant quasi-optical devices.

Multilayer Grid Polarizers: Simulations for Millimeter Waves

“…At the same time, any waves are allowed to leave the domain with no obstruction. In a similar way, the radiation condition is imposed at the rear surface behind the structure (x = X R ) where no incoming wave should enter the domain [30]. The conditions at the side borders are defined at y = ±Y s in a symmetric manner assuming that an integer number of grating periods are included in the domain, and no waves propagate across the borders.…”