Dynamic control of slow light pulses in photonic crystal waveguides

Lattice-shifted photonic crystal waveguide generates low-dispersion slow light for nonlinear enhancement and dispersion-compensated slow light for tunable delay. The low-dispersion slow light at a fiber communication wavelength produces efficient two-photon absorption and carrier plasma dispersion (CPD) when the waveguide is fabricated into Si. This presentation demonstrates the following three functions obtained with such two slow light pulses: 1) adiabatic wavelength conversion, 2) pulse compression, and 3) ultrafast delay tuning. For 1), we show that co-propagating two slow light pulses break the limit of the conventional adiabatic wavelength conversion using a resonator. For 2), a compression factor of 3.3 is demonstrated using the CPD and heater-controlled dispersion compensator. For 3), the delay of the signal pulse is shifted up to 10 ps with a switching time as short as 10 ps, which enables the selective delay tuning of one pulse in a high-speed pulse train.