Response-time improvement of a 2×2 thermo-optic switch with polymer/silica hybrid waveguide

A polymer/silica hybrid 2×2 directional coupler (DC) Mach–Zehnder interferometer (MZI) thermo-optic (TO) switch is designed and carefully fabricated. Because of larger thermal conductivity relative to the polymer, silica is utilized as bottom cladding for accelerating heat release. The fabricated TO switch with polymer/silica hybrid structure exhibits low power consumption, less than 7.2 mW, fast rise time of about 106 μs and fast fall time of about 93 μs. This response time is reduced by 40% compared to that of the TO switch with polymer waveguide.