Up to 8-GHz Ultrafast Multi-Wavelength Routing Operation of Active Birefringent Fiber Loop Filter/Interleaver Using a Traveling-Wave-Type Phase Modulator

Ultrafast multi-wavelength routing by an active birefringent fiber loop filter/interleaver is proposed and demonstrated. In the proposed active filter, the loop part consists of a birefringent optical fiber and a traveling-wave-type phase modulator. Numerical simulation using Jones matrix analysis shows that the periodic transmission/reflection bands of the filter can be switched by changing a phase difference between clockwise and counter clockwise components passing through the birefringent fiber loop. Experimentally, we realize fast switching by controlling the applied voltage to the phase modulator, and 8-GHz wavelength routing operation is achieved.