Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: An improved semiconductor laser (distributed feedback or Bragg reflector laser) is disclosed, having reducing wavelength chirping. In a laser having a substrate, an optical waveguide layer disposed on the substrate with a grating region, and a cladding region disposed on the optical waveguide layer, an isolation region is positioned in at least one of the substrate, optical waveguide layer, and cladding layer. The isolation region is comprised of a material adapted to increase the resistivity of the one or more layers in which it is placed to reduce electrical cross-talk and wavelength chirping. Preferably, the isolation region is positioned in at least the cladding layer, which the inventors have found is the greatest contributor of cross-talk and wavelength chirping.

Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: A low threshold distributed feedback (DFB) laser is constructed for improved performance at subzero temperatures. A loss grating is employed to enhance the probability that lasing occurs near the short wavelength side of the stopband and to counteract the effect of negative gain tilt that occurs when DFB lasers are positively detuned. A method of making DFB lasers from wafers with improved yield for low temperature side mode suppression ratio (SMSR) is also disclosed.

Abstract: The invention is an assembly and method for bonding an optical component to a base member. The component is mounted to a block which includes a centerline extending between two opposing surfaces. A pair of stop members are included on the surface of the base member, and these members serve to pin the centerline during heating and cooling of the assembly so that the position of the component is controlled.

Abstract: A method for maximizing the coupling efficiency of a fabricated fiber-optic laser module by deforming the module. In a first embodiment, the method can use a plurality of previously determined influence coefficients to determine how to deform the module, wherein such deformation aligns the focal point of the optical fiber and the laser to maximize the coupling efficiency. Alternatively, in a second embodiment of the present invention, the method is implemented without the use of influence coefficients, wherein the changes in the coupling efficiency resulting from deforming the module are observed to determine which deformations will maximize the coupling efficiency. Irrespective of which embodiment of the present invention is used, the module is deformed to account for its elastic properties by deforming the module beyond the final shape it attains when the coupling efficiency is maximized.

Abstract: A stable, reliable ohmic contact, and improved semiconductor articles and opto-electronic circuits incorporating same, are disclosed. According to an illustrative embodiment of the invention, an ohmic contact having a plurality of thermodynamically-stable layers and layer interfaces is formed by providing a structure comprising multiple, appropriately-thick and specifically-organized layers of suitably-selected material, and exposing the structure to heat to cause reaction to take place between the various layers. Due to the thermodynamic stability of the resulting reacted layers and the interfaces between such layers, there is substantially no tendency for further reaction to occur within the ohmic contact.

Abstract: The invention is an assembly and method for bonding an optical component to a base member. The component is mounted to a block which includes a centerline extending between two opposing surfaces. A pair of stop members are included on the surface of the base member, and these members serve to pin the centerline during heating and cooling of the assembly so that the position of the component is controlled.

Abstract: The invention is a laser with improved turn-on time for digital applications. The low bias capacitance effect of the laser is reduced by use of a buffer region formed between the substrate and the active region, the buffer region having a lower dopant concentration than the substrate.