Polymer 1×2 thermo-optic digital optical switch based on the total-internal-reflection effect

This letter presents a polymer 1×2 thermo-optic totalinternal- reflection digital optical switch (TIR-DOS) with an index contrast of 1.5%-Δ operating at low power consumption. The structure of our 1×2 TIR-DOS was created by adding a reflection port to that of a conventional multimode filtering variable optical attenuator. To improve the total-internalreflection efficiency, a heater offset was applied to the crossing region of multimode waveguides of the TIR-DOS. The fabricated 1×2 TIR-DOS shows a low electrical power consumption of 18 mW for an on-off ratio of 35 dB.