Silica Waveguide DQPSK Demodulator With Wide Operation Range Enhanced by Using Stress Release Grooves

A 43-Gb/s differential quadrature phase-shift keying demodulator is demonstrated with a wide operation range enhanced by birefringence control achieved by using stress release grooves. The fabricated demodulator realizes a sufficiently low polarization-dependent frequency shift of less than 150 MHz over the C- and L-bands. In addition, we report an experimental result showing the reduction in the power consumption of a thermooptic effect-based phase shifter achieved by introducing the grooves.