Alfredo De Rossi

Advances in III-V based photonic crystals for integrated optical processing

Compactness, massive integration of multiple functions on a single chip and power consumption are crucial for transmission of large aggregated bit rates at short distance. Efficient implementation of data processing at the optical level are very attractive. Here we present a technology for implementing ultra-fast switching with recordlow energy·recovery time product. We developed high-quality photonic crystal micro-resonators based on III-V semiconductors. The very short carrier lifetime of nano-pattened Gallium Arsenide enabled us to achieve 6 ps recovery time, thus enabling operations beyond the 100Gb/s rate. For broadband operation, highly nonlinear waveguides with low insertion loss have been demonstrated.

Nanophotonic Approach to Energy-Efficient Ultra-Fast All-Optical Gates

All-optical processing is based on fast nonlinear effects, such that light can be used to control light. The development of a novel class of low-loss semiconductor optical resonators, capable of field confinement close to the diffraction limit, has decreased the power level required to trigger nonlinear effects by several orders of magnitude. We review a decade of research on all-optical gates aiming both at fast and energy-efficient operation, with the prospect of integration on a silicon photonics platform.

Control of dispersion in photonic crystal waveguides using group symmetry theory

We demonstrate dispersion tailoring by coupling modes in a photonic crystal waveguide. Different dispersion features are generated and controlled by a single geometrical parameter. This concept is demonstrated experimentally with very good agreement with theory.