Nonlinear optical properties of an InGaAs/InAlAs multiple quantum well waveguide with pulsed excitation

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