Fast polymer thermo-optic switch with silica under-cladding

A polymer/silica hybrid 2 × 2 multimode-interference Mach-Zehnder interferometer thermo-optic (TO) switch is designed and fabricated. Silica is adopted as the under-cladding to accelerate heat release for its large thermal conductivity. The fabricated switch exhibits low power consumption of 6.2 mW, low crosstalk of -28 dB, and fast speed. The rise and fall times of this hybrid switch are 103 and 91 μs, respectively. Comparing with the fabricated TO switch (174 and 191 μs) using polymer as both upper-cladding and under-cladding, response times of this hybrid one are shortened by 40.8% and 52.4%, respectively.