Low electric power drived thermo-optic multimode interference switches with tapered heating electrodes

A novel thermo-optic multimode interference (MMI) switch with a tapered heating electrode was proposed and the performance of the switch was simulated. An analytical steady-state heat-conduction model is also presented. In the design, one tapered heating electrode is used to alter the refractive index in the multimode slab region to realize the switching function. The simulation results indicate that the MMI switch can provide high extinction ratio, and good polarization- and wavelength-independence. The electric power consumption for the MMI switch is half of that of a switch with a straight heating electrode and similar to that of a Mach-Zehnder interferometer switch.