Study on S/N-ratio characteristics by coherent crosstalk of Mach-Zehnder Interferometer-type photonic switch

We analyzed S/N-ratio characteristic by coherent crosstalk of 2×2 and 4×4-cascaded Mach-Zehnder Interferometer-type photonic switches. The S/N ratios by the coherent crosstalks are as high as 25[dB] and 28[dB] for 2×2 and 4×4-cascaded switches, respectively, under the optimal MMI width conditions.