DESIGN OF WAVE-GUIDE GRATING BASED ON SIMULATED ANNEALING AND NARROW-BAND MODULATION

A new method for designing optical waveguide grating structures by an optimization technique is proposed based on the concept of narrow-band modulation. A grating profile is considered as a high-frequency periodic grating modulated by a slowly varying binary function. To make the optimization algorithm as robust as possible, a digital vector is introduced to describe the binary function, and simulated annealing is employed to perform the optimization. Several examples of grating design are given. They show that the method offers a great freedom with the least human intervention, for designing a variety of reflection characteristics that are significantly different from those of conventional grating structures.