All-optical logical operation in photonic wire nano-cavities

In the present work the authors demonstrate the possibility to perform logical AND operations and NOT operations based on all-optical switching in a 1D photonic crystal (PhC) tapered nanocavity fabricated in SOI silicon photonic wire (PhW) waveguide. After an initial characterization of the optical response of the system by means of linear waveguide transmission, all-optical logical operations were achieved by carefully tuning the probe wavelength across the device resonance with very low power, employing free-carrier generation as the physical mechanism to modify the optical response of a high-Q cavity mode.