All-Optical Switching in InGaAsP–InP Photonic Crystal Resonator Coupled With Microfiber

We demonstrated high-efficiency all-optical switching in an InGaAsP–InP photonic crystal resonator evanescently coupled with a microfiber. The nonlinearity was based on carrier injection by single-photon absorption of 980-nm pump light. Carrier-induced and thermally induced shifts of resonance wavelengths were observed under continuous-wave pumping. In pulse operation, an instantaneous refractive index change of n 0:0035 and 1.5-nm blueshift of the resonant wavelength were achieved with pump energy of 300 fJ, resulting in switching of the transmission output with 50% ON–OFF contrast. This fiber-based configuration provides a quick and effective means for the study of optical nonlinearities in microcavities.