Bistable switching and reshaping of optical pulses in a Bragg grating cavity

We experimentally demonstrate switching of the transmission of a nanosecond optical pulse in a nonlinear Bragg grating cavity. The grating is designed with a π phase-shift in the center, which forms the cavity and enhances intensity by a factor of 45. For a high-intensity input pulse detuned from the resonance, we observe significant temporal reshaping of the output pulse: the output waveform becomes asymmetric with a sharp leading edge and an extended tail. Although the nonlinearity of a silica glass is ultrafast, the time scale of dynamic effects is determined by the linear and nonlinear cavity response times, which are tens of picoseconds. More generally, the asymmetric pulse shape such as the one presented here is expected to be a feature of all-optical self-switches based on high finesse cavities.