NONLINEAR-OPTICAL PROPERTIES OF AN INGAAS INALAS MULTIPLE-QUANTUM-WELL WAVE-GUIDE WITH PULSED EXCITATION/

Large optical refractive nonlinearity in a passive InGaAs/InAlAs multi ple quantum well waveguide is demonstrated at a wavelength of 1.55 mum by observing a shift in the transmission fringe of a Fabry-Perot reso nator with a pulsed pump beam. In a 650-mum long resonator, a half pi phase shift every 3.3 mW with increasing in pump beam power is observe d up to 4pi. The response time of the nonlinear refractive index chang e is estimated to be 1 ns.