Optimizing integrated-optics polarizers for maximum polarization isolation

Available technologies currently permit the construction of optical integrated polarizers employing accurate features with dimensions considerably smaller than the operation wavelength. These devices may have a relatively small number of grooves and rely on the wave-polarization dependence of the groove scattering to achieve their results. To achieve optimum performance (e.g., maximum polarization isolation) they must be modeled with an accuracy only possible through the use of rigorous vector diffraction theory. One such technique is applied to analyze and design perfectly conducting polarizers with finite number of arbitrarily-shaped features. The currents flowing on the grooves´ surfaces are rigorously obtained, and from them the scattered field is determined. As an application example, the dimensions of the first and last grooves of a 20-triangular-grooves polarizer, operating at 1 μm wavelength, are optimized to yield a polarization isolation of 57 dB