Influence of two-photon absorption and free-carrier effects on all-optical logic gates in silicon waveguides

Abstract

We investigate the impact of two-photon absorption (TPA) and free-carrier effects on all-optical logic gates in silicon waveguides, in which the conversion efficiency is greatly reduced and the waveform is seriously distorted. A silicon–organic hybrid dual-slot waveguide without TPA is proposed for all-optical logic gates and could offer an extremely large nonlinear parameter higher than 1.4 × 107 W−1 km−1. The all-optical logic AND, OR, and XOR gates based on four-wave mixing in this waveguide are realized for 100 Gb s−1 data signals in the C-band. These results provide potential applications for all-optical signal processing in integrated optics, optical communications, and optical computation.