Improved Optical 1xN On-Chip-Switches Based on Generalized Mach-Zehnder Interferometers

We present a theoretical study of 1xN optical routing networks consisting of generalized Mach-Zehnder switches, that are based on multimode interferometers. This work gives a brief overview of the necessary phase conditions and resulting phase shifter requirements in the 1xN switches. Using the presented approach as 1x4 switch with parallel phase shifters, a 20% phase-shifter-loss reduction becomes possible.