Optimal design of microscaled scattering optical elements -: art. no. 193506

A method of inverse design is applied to generate an optical device that acts as a wavelength demultiplexer. The ultracompact device, only 2 mu m thick, is designed to separate two wavelengths 1.55 mu m and 1.50 mu m, respectively, and consists of five layers of 0.4 mu mx0.4 mu m square-shaped bars etched in gallium arsenide. The expected cross talk is suppressed below -25 dB for both wavelengths. The proposed device is an example of a scattering optical element, a name here introduced to define a class of computer-generated optical devices and whose functionalities are based on the multiple scattering by their individual constituents. For realization of the aforementioned devices, two-dimensional photonic plates can be prepared by only a single integrated circuit processing procedure followed by micromanipulation assembling. (C) 2005 American Institute of Physics.