Abstract: A semiconductor optical amplifier (SOA) with efficient current injection is described. Injection current density is controlled to be higher in some areas and lower in others to provide, e.g., improved saturation power and/or noise figure. Controlled injection current can be accomplished by varying the resistivity of the current injection electrode. This, in turn, can be accomplished by patterning openings in the dielectric layer above the current injection metallization in a manner which varies the series resistance along the length of the device.

Abstract: High power, low degree of polarization superluminescent diodes (SLDS) are described. A semiconductor optical amplifier (SOA) which amplifies light in substantially one polarizaton state can be used to create a SLD by combining the output from both sides of this polarization sensitive SOA in a manner which results in a depolarized output.

Abstract: Optical modulators with reduced temperature dependence on bias control are described. A set of bias electrodes is arranged relative to a set of RF electrodes in a manner which results in the opening point of the device remaining relatively constant as a function of temperature. The arrangement of the bias electrodes relative to the RF electrodes includes a physical offset of one set of electrodes relative to the other, with or without a reversal of polarity of one set of electrodes relative to the other. Arrangements according to the present invention create a symmetrical electrode arrangement from a temperature-induced stress point of view so that the operating point of the device remains relatively constant as a function of temperature.