All-optical switching in phase-shifted fiber Bragg grating

A low-power all-optical-switching in a phase-shifted grating has been experimentally demonstrated at 1.55 μm. The grating is written in a standard fiber for communication and the switching is based on the cross-phase modulation induced by an intense pump pulse on a low intensity probe. An extinction ratio of more than 6 dB has been achieved for 1 kW pulse peak power. The strong enhancement of the nonlinear effect due to the group velocity reduction and the switching polarization dependence have been theoretically investigated and experimentally confirmed.