Synthesizing ideal windowlike spectral response in codirectional grating-assisted couplers is considered. The method of variational optimization is used to design couplers theoretically with near 100% power transfer efficiency over the passband width and with sidelobes suppressed to -40 dB. The physical role of the π-phase-reversal sections for passband f lattening is explained.
© 1996 Optical Society of America
Brent E. Little, Chi Wu, and Wei-Ping Huang, "Synthesis of ideal window filter response in grating-assisted couplers," Opt. Lett. 21, 725-727 (1996)