Effect of Coupled Double-Quantum-Well Design on Pump-Induced Refractive-Index Change in AlAsSb–InGaAs–AlAs Optical Waveguides

Optimization of the AlAsSb-InGaAs-AlAs coupled double-quantum-wells in optical waveguide core for optimal pump-induced refractive-index change indicates that thin AlAs center barrier leads to larger refractive-index change, and the InGaAs double-quantum-wells have an optimum thickness of which maximum refractive-index change is obtained. Analysis shows that the cross phase-modulation efficiency of these optical waveguides is highly dependent on optical confinement and is limited to approximately 0.05 rad/pJ in the 1550 nm region as far as the cross phase-modulation based on free-carrier mass dispersion effect is concerned.