Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate a propagation of an optical signal therethrough; a segmented traveling wave electrode structure comprising electrode segments disposed on the optical waveguide; and an electrical transmission line operatively coupled to the electrode segments via conducting bridges, wherein the electrical transmission line is configured to facilitate a propagation of an electrical signal therethrough, wherein the electrode segments are configured to overcome bandwidth and extinction ratio constraints of a lumped EAM.

Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate propagation and modulation of an optical signal therethrough; a segmented structure comprising diode segments disposed on the waveguide; and an electrical transmission line operatively coupled to the diode segments. The electrical transmission line is configured to facilitate propagation of an electrical signal therethrough. The electrical transmission line includes a first transmission line rail and a second transmission line, where a first subset of diode segments is operatively coupled to the first transmission line rail and a ground rail, and a second subset of diode segments is operatively coupled to the second transmission line and the ground rail. The diode segments from the first subset are disposed alternately with the diode segments from the second subset.

Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate a propagation of an optical signal therethrough; a segmented traveling wave electrode structure comprising electrode segments disposed on the optical waveguide; and an electrical transmission line operatively coupled to the electrode segments via conducting bridges, wherein the electrical transmission line is configured to facilitate a propagation of an electrical signal therethrough, wherein the electrode segments are configured to overcome bandwidth and extinction ratio constraints of a lumped EAM.

Abstract: High bandwidth (e.g., >100 GHz) modulators and methods of fabricating such are provided. An EAM comprises a waveguide mesa comprising a continuous multi-quantum well (MQW) layer; a plurality of electrode segments disposed on the waveguide mesa; and a microstrip transmission line disposed on an insulating material layer and in electrical communication with the plurality of electrode segments via conducting bridges. The waveguide mesa comprises alternating active sections and passive sections. An electrode segment of the plurality of electrodes is disposed on a respective one of the active sections. Portions of the continuous MQW layer disposed in each of the active sections having an energy gap defining an active energy gap value. Portions of the continuous MQW layer disposed in each of the passive sections having an energy gap defining an passive energy gap value. The active energy gap value is less than the passive energy gap value.

Abstract: Various embodiments provide a PIN-photodetector configured to detect light characterized by a particular wavelength range. The photodetector includes an absorber region including a material having an absorption coefficient of greater than 104 cm?1 in the particular wavelength range. The absorber region has an absorber thickness in a direction that is substantially parallel to a detection axis of the photodetector. The photodetector further includes a collector region including a material that is substantially transparent to the particular wavelength range. The collector region has a collector thickness in the direction that is substantially parallel to the detection axis. The collector thickness is greater than the absorber thickness. The absorber region does not spatially overlap with the collector region. The photodetector is configured to operate at a bandwidth of at least 50 GHz.

Abstract: Various embodiments provide a PIN-photodetector configured to detect light characterized by a particular wavelength range. The photodetector includes an absorber region including a material having an absorption coefficient of greater than 104 cm?1 in the particular wavelength range. The absorber region has an absorber thickness in a direction that is substantially parallel to a detection axis of the photodetector. The photodetector further includes a collector region including a material that is substantially transparent to the particular wavelength range. The collector region has a collector thickness in the direction that is substantially parallel to the detection axis. The collector thickness is greater than the absorber thickness. The absorber region does not spatially overlap with the collector region. The photodetector is configured to operate at a bandwidth of at least 50 GHz.

Abstract: Approaches presented herein provide for the reduction of unwanted electrical reflections caused by impedance mismatches at an input of an optical modulator device, such as at the interface between a (radio frequency) signal source and an electro-absorption modulated laser (EML). Reflections can be reduced though use of one or more electrical filters, such as resistor-capacitor (RC) filters, that can be placed at the input of the EML device to reduce reflections through impedance matching at that location, while maintaining the efficiency and bandwidth of the modulator for high bandwidth transmission. Such a filter can be used with a single ended or differential EML device, and can be integrated on an EML chip or added as discrete components on a chip carrier on which the EML chip is supported.

Abstract: Systems and methods are directed localized heating for a modulator incorporated into an electro-absorption modulated laser (EML). A heater may be positioned proximate one or more portions of the modulator to apply heat energy to the modulator responsive to an input. The heater may be configured to apply a dissipation of heat so that the modulator operates within a selected temperature range. The modulator and/or the heater may be thermally insulated, at least in part, from a substrate associated with the EML by one or more low thermal conductivity layers arranged between the modulator and a substrate of the EML.

Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate propagation and modulation of an optical signal therethrough; a segmented structure comprising diode segments disposed on the waveguide; and an electrical transmission line operatively coupled to the diode segments. The electrical transmission line is configured to facilitate propagation of an electrical signal therethrough. The electrical transmission line includes a first transmission line rail and a second transmission line, where a first subset of diode segments is operatively coupled to the first transmission line rail and a ground rail, and a second subset of diode segments is operatively coupled to the second transmission line and the ground rail. The diode segments from the first subset are disposed alternately with the diode segments from the second subset.

Abstract: Processes and devices for continuous compositional grading in photodetectors and electro-absorption modulators (EAM) are provided. An example photodetector includes a multi-layered structure comprising a collector region, an absorber region, a grading layer, and a peripheral layer, all aligned along a detection axis. The grading layer, positioned adjacent to the absorber region, includes multiple sub-layers that define a continuous compositional grading to facilitate smooth carrier transport and reduce recombination. Similarly, an example electro-absorption modulator (EAM) device includes a waveguide mesa formed on a semiconductor substrate, comprising a multi-quantum well (MQW) core layer, upper and lower near-core cladding layers, and upper and lower central cladding layers. The EAM device features both upper and lower grading layers, each positioned between the near-core cladding layers and the adjacent central cladding layers.

Abstract: Methods of forming a graphene integrated core for making a printed circuit board (PCB) having enhanced thermal management properties are disclosed. The methods include providing a core body having a core body length and applying a graphene multi-layer to the core body to form a laminated stack, where the graphene multi-layer has a graphene multi-layer length that is shorter than the core body length. At least one conductive layer may be applied to the laminated stack. The graphene multi-layer may be disposed within the graphene integrated core such that the graphene multi-layer is electrically insulated from the at least one conductive layer. Corresponding graphene integrated cores having a graphene multi-layer that is disposed within the graphene integrated core such that the graphene multi-layer is electrically insulated from the at least one conductive layer are also described.

Abstract: Methods for integrating copper-graphene laminate (CGL) in a multilayer PCB fabrication process and the resulting lamination stacks are disclosed. The methods include providing a core and applying a first graphene layer to the surface of the core. The methods further include applying a metal layer to the first graphene layer and applying a second graphene layer to the metal layer. Further, the methods include applying a photoresist layer to the second graphene layer and applying a protective layer to the photoresist layer. In some embodiments, the methods include applying a metallic plating to lamination stack. The methods further include drilling through the protective layer and at least one of a photoresist layer, the second graphene layer, the metal layer, the first graphene layer, and/or the core.

Abstract: Processes for continuous compositional grading for realization of low charge carrier barriers in electro-optical heterostructure semiconductor devices are provided. An example process includes forming, onto one or more semiconductor layers of an electro-optical semiconductor device, a first semiconductor layer associated with a first bandgap value and forming, onto the first semiconductor layer, a grading layer associated with a continuous compositional grading. The example method further includes forming, onto the grading layer, a second semiconductor layer associated with a second bandgap value. The second bandgap value is different than the first bandgap value.

Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate a propagation of an optical signal therethrough; a segmented traveling wave electrode structure comprising electrode segments disposed on the optical waveguide; and an electrical transmission line operatively coupled to the electrode segments via conducting bridges, wherein the electrical transmission line is configured to facilitate a propagation of an electrical signal therethrough, wherein the electrode segments are configured to overcome bandwidth and extinction ratio constraints of a lumped EAM.

Abstract: Systems and methods are described herein for an electro-absorption modulator (EAM) device. An example EAM device comprises an optical waveguide comprising a waveguide core configured to facilitate propagation of an optical signal therethrough; a segmented structure comprising diode segments disposed on the waveguide; and a differential electrical transmission line operatively coupled to the diode segments. The electrical transmission line includes a first transmission rail and a second transmission rail, and the electrical transmission line is configured to facilitate propagation of an electrical signal therethrough. The EAM device is configured for operation by a differential radio frequency (RF) source that is configured to supply the electrical signal to the EAM device, and the EAM device is formed on a semi-insulating substrate.

Abstract: Processes for continuous compositional grading for realization of low charge carrier barriers in electro-optical heterostructure semiconductor devices are provided. An example process includes forming, onto one or more semiconductor layers of an electro-optical semiconductor device, a first semiconductor layer associated with a first bandgap value and forming, onto the first semiconductor layer, a grading layer associated with a continuous compositional grading. The example method further includes forming, onto the grading layer, a second semiconductor layer associated with a second bandgap value. The second bandgap value is different than the first bandgap value.

Abstract: Photodetectors configured to detect light in a particular wavelength range and including a quaternary material are described herein. In some embodiments, the present invention may be directed to a photodetector that includes a collector material that is substantially transparent to the particular wavelength range and a quaternary material adjacent to the collector material, where the quaternary material functions as an absorber material and is lattice-matched to the collector material. A conduction band difference between the collector material and the quaternary material may be approximately zero. Additionally, or alternatively, the photodetector may include a peripheral layer adjacent to the quaternary material, where the peripheral layer is doped with carbon. In some embodiments, the photodetector may include an optical window configured for use with a multi-mode optical fiber.

Abstract: High bandwidth (e.g., > 100 GHz) modulators and methods of fabricating such are provided. An EAM comprises a waveguide mesa comprising a continuous multi-quantum well (MQW) layer; a plurality of electrode segments disposed on the waveguide mesa; and a microstrip transmission line disposed on an insulating material layer and in electrical communication with the plurality of electrode segments via conducting bridges. The waveguide mesa comprises alternating active sections and passive sections. An electrode segment of the plurality of electrodes is disposed on a respective one of the active sections. Portions of the continuous MQW layer disposed in each of the active sections having an energy gap defining an active energy gap value. Portions of the continuous MQW layer disposed in each of the passive sections having an energy gap defining an passive energy gap value. The active energy gap value is less than the passive energy gap value.

Abstract: A method for efficient heat removal from a semiconducting device made from III-V semiconductor crystals includes depositing a diamond seeding layer on a patterned substrate.

Abstract: Various embodiments provide a PIN-photodetector configured to detect light characterized by a particular wavelength range. The photodetector includes an absorber region including a material having an absorption coefficient of greater than 104 cm?1 in the particular wavelength range. The absorber region has an absorber thickness in a direction that is substantially parallel to a detection axis of the photodetector. The photodetector further includes a collector region including a material that is substantially transparent to the particular wavelength range. The collector region has a collector thickness in the direction that is substantially parallel to the detection axis. The collector thickness is greater than the absorber thickness. The absorber region does not spatially overlap with the collector region. The photodetector is configured to operate at a bandwidth of at least 50 GHz.