Fluorinated polyimide waveguides with low polarization-dependent loss and their applications to thermooptic switches

Fluorinated polyimide waveguides with low polarization dependent loss (PDL) and thermooptic (TO) switches made from them were demonstrated. The waveguides showed loss of less than 0.3 dB/cm at the wavelength of 1.3 /spl mu/m and 0.6 dB/cm at 1.55 /spl mu/m for both TE and TM polarizations. The PDL's were less than 0.1 dB/cm. Extinction ratios of Y-branching-type TO switches fabricated from these waveguides were larger than 20 dB when over 160 mW of electric power was applied at 1.3 /spl mu/m, and over 150 mW at 1.55 /spl mu/m. The switching speed was faster than 8 ms.