Ultra-broadband low-loss 2×2 MZI (Mach-Zehnder interferometer)-based thermo-optic switch with bent directional couplers on silicon

A low-loss and broadband silicon-based thermo-optic Mach-Zehnder switch (MZS) is proposed and demonstrated with 2×2 3dB bent directional-couplers. The demonstrated MZS has a ~140nm bandwidth for excess loss of <;1dB and extinction ratio of >20dB.