Semiconductor optical amplifiers will be important components in future optical communication and photonic switching systems. In this proposal, an experimental study of the potential of using both Fabry- Perot and traveling-wave laser amplifiers for enlarging the bandwidth of present fiber optic systems is proposed. In particular, this is a study of the problem of crosstalk, gain saturation, sensitivity and fidelity of both Fabry-Perot and traveling-wave laser amplifiers for the amplification of ultra high data rates intensity modulated wavelength multiplexed signals. In collaboration with Harry Diamond Laboratories, the principal investigator also proposes to fabricate waveguides and to optimize the optical coupling efficiency of bistable diode laser amplifiers in an out-of-plane addressing configuration by using 45o-angle mirrors and gratings fabricated with a focused ion beam. These technical objectives complement this work on photonic switching devices and, at the same time, support and enhance similar thrusts of the Harry Diamond Laboratories optoelectronic program. In addition, he proposes to use the technique of in-situ ellipsometry for monitoring the deposition of anti-reflection coatings on the facets of a commercially available diode laser. This will ensure the reproducible making of high-quality traveling-wave laser amplifiers.