Resonant nonlinear optical properties of GaAs-GaAlAs single quantum-well waveguide and an integrated asymmetric Mach-Zehnder interferometer

The resonant refractive and absorptive optical nonlinearities of a GaAs-AlGaAs single quantum-well waveguide are characterized. The recovery time of the absorptive nonlinearity is measured as 125 ps. All-optical operation of an integrated asymmetric Mach-Zehnder interferometer is demonstrated, using intense approximately 50-ps pulses from a mode-locked Ti:sapphire laser. The device operation is detrimentally affected by thermally induced changes in the refractive index even in a 50 ps timescale.>