Grating-type polarizers using small number of rectangular grooves optimized for maximum isolation

Integrated circuit technology permits the etching of metalized gratings within an overall accuracy better than O.1 /spl mu/m. This allows for mass production of very accurate gratings that can be used for polarization control and separation at terahertz frequencies and beyond. The paper is concerned with determining the profile of polarizing gratings for operation at terahertz frequencies (and higher), in order to obtain optimum electrical performance with a relatively small number of grooves. The gratings are assumed to have a finite number of infinitely-long metalized rectangular grooves illuminated by a plane wave. Two-dimensional integral equations are used to rigorously formulate the scattered field problem. These equations are then solved using standard method-of-moments techniques. As a case study, the electromagnetic scattering of a finite grating with two rectangular grooves per grating period is analyzed and optimized for maximum polarization isolation.