Abstract
We report time-resolved studies of transient gratings in room-temperature GaAs/AlGaAs multiple-quantum-well structures made using a subpicosecond laser system. Forward-traveling and counterpropagating four-wave mixing geometries produced carrier modulation either parallel or perpendicular to the quantum wells such that the highly anisotropic carrier diffusion could be monitored. Carrier heating and cross-well transport was monitored and geometrical control of the diffusion and resulting four-wave mixing time constant demonstrated. Measured diffraction efficiencies gave the refractive-index change of the order of Δn ~ 0.02 at the onset of saturation of the heavy-hole exciton nonlinearity. Implications for refractive optical bistability are discussed through a determination of the limiting conditions for switching.
© 1989 Optical Society of America
Full Article | PDF ArticleMore Like This
R. H. M. Groeneveld and D. Grischkowskyt
J. Opt. Soc. Am. B 11(12) 2502-2507 (1994)
D. S. Chemla and D. A. B. Miller
J. Opt. Soc. Am. B 2(7) 1155-1173 (1985)
J. Hegarty and M. D. Sturge
J. Opt. Soc. Am. B 2(7) 1143-1154 (1985)