Abstract: Optical waveguides may include a substrate and a silicon based optical waveguide supported on the substrate. The silicon based optical waveguide may include a central ridge portion and a plurality of spaced apart wing portions connected through connecting portions. The number of wing portions may be greater than two. The central ridge portion may have a central ridge lateral width extent greater than a lateral width extent of at least one of the wing portions. Optical waveguides may include a substrate, a silicon based optical waveguide supported on the substrate, and a concentrator supported on the substrate and positioned within a lateral width extent of the silicon based optical waveguide and outside of a height extent of the silicon based optical waveguide. The optical waveguides may be included as part of an optical modulator.

Abstract: A system and method for controlling optical receiver operation in response to a received optic signal power level that includes providing an optic signal receiver having operation determined by one or more system settings. During operation, the optic signal is received and converted to an electrical signal. The electrical signal is evaluated to determine a power level of the electrical signal. Responsive to the power level of the electrical signal exceeding a first predetermined threshold, adjusting a first system setting and responsive to the power level of the received electrical signal decreasing below a second predetermined threshold, adjusting the first system setting. Then, responsive to the power level of the received electrical signal exceeding a third predetermined threshold, adjusting a second system setting and responsive to the power level of the received electrical signal decreasing below a fourth predetermined threshold, adjusting the second system setting.

Abstract: Semiconductors lasers are disclosed having an active region having a longitudinal axis, a first facet end, and a second facet end. The second facet end emitting the main output beam of light from of the respective semiconductor laser. The first facet end may have a low-reflection coating. The first facet end may be non-perpendicular to the longitudinal axis of the active region. The semiconductor lasers may be distributed feedback (DFB) lasers having a plurality of diffraction gratings along the longitudinal axis of the active region. The plurality of diffraction grating may include a first diffraction grating positioned proximate the first end of the active region, a second diffraction grating positioned proximate the second end of the active region, and a third diffraction grating positioned between the first diffraction grating and the second diffraction grating.

Abstract: A method and apparatus for adapting an equalizer coefficients to a channel comprising filtering a high frequency error monitor slicer output and a data slicer output to isolate selected high frequency symbol values. Filtering a low frequency error monitor slicer output and the data slicer output to isolate selected low frequency symbol values. Generating a high frequency error monitor slicer threshold signal with a first adaptation module. Generating a low frequency error monitor slicer threshold signal with the first adaptation module or a second adaption module. Combining the high frequency error monitor slicer threshold signal and the low frequency error monitor slicer threshold signal to generate a difference signal. Integrating the difference signal with an accumulator to generate equalizer coefficients to adapt the equalizer to the channel. Providing the high frequency and low frequency error monitor slicer threshold signal to respective slicers.

Abstract: A communication interface comprising a host with non-linear equalizers configured to perform non-linear equalization. Also part of the interface is a host to optic module channel electrically connecting the host to an optic module and the optic module. The optic module comprises a transmitter and a receiver. The transmitter includes a linear equalizer and an electrical to optical module configured to convert the equalized signal from the driver to an optical signal, and transmit the optical signal over a fiber optic cable, such that the transmitter does not perform non-linear processing. The receiver includes a photodetector, configured to convert the received optic signal to a received electrical signal, and a linear amplifier configured to perform linear amplification on the received electrical signal. A driver sends the amplified received signal over an optic module to host channel, such that the receive does not perform non-linear processing.

Abstract: A multicomponent network may be added to a transmission line in a high-frequency circuit to transform a first impedance of a downstream circuit element to second impedance that better matches the impedance of an upstream circuit element. The multicomponent network may be added at a distance more than one-quarter wavelength from the downstream circuit element, and can tighten a frequency response of the impedance-transforming circuit to maintain low Q values and low VSWR values over a broad range of frequencies.

Abstract: A semiconductor laser may include an active region having a longitudinal axis, a rear facet end and a front facet end. The front facet end emitting an output beam of the semiconductor laser. The semiconductor laser may include a plurality of diffraction gratings positioned along the longitudinal axis of the active region. The plurality of diffraction gratings including a first diffraction grating positioned proximate the rear facet end of the active region and at least one additional diffraction grating positioned longitudinally between the first diffraction grating and the front facet. The first diffraction grating having a first kappa value and the at least one additional diffraction grating having at least a second kappa value, the first kappa value being greater than the second kappa value.

Abstract: Systems and methods are provided to align a first optical component carried by a first semiconductor chip with a second optical component carried by a second semiconductor chip. Each of the first semiconductor chip and the second semiconductor chip may include at least one primary semiconductor chip fiducial which assists in the alignment of the first optical component carried by a first semiconductor chip with a second optical component carried by a second semiconductor chip.

Abstract: Examples of integrated semiconductor devices are described. In one example, an integrated device includes first and second transistors formed on a substrate, where the transistors share a terminal metal feature to reduce a size of the integrated device. The terminal metal feature can include a shared source electrode metalization, for example, although other electrode metalizations can be shared. In other aspects, a first width of a gate of the first transistor can be greater than a second width of a gate of the second transistor, and the shared metalization can taper from the first width to the second width. The integrated device can also include a metal ground plane on a backside of the substrate, and the terminal metal feature can also include an in-source via for the shared source electrode metalization. The in-source via can electrically couple the shared source electrode metalization to the metal ground plane.

Abstract: Systems and methods are provided to align a first optical component carried by a first semiconductor chip with a second optical component carried by a second semiconductor chip. Each of the first semiconductor chip and the second semiconductor chip may include at least one primary semiconductor chip fiducial which assists in the alignment of the first optical component carried by a first semiconductor chip with a second optical component carried by a second semiconductor chip.

Abstract: A shared bus for inter-channel communication comprising two or more channels having signal processing elements such that each channel is configured to receive and process an incoming channel specific signal. A sequence generator is configured to generate a test sequence suitable for testing the signal processing elements of a channel. An error checker is configured to error check incoming channel specific signals. A shared bus connects to the two or more channels to communicate an incoming channel specific signal to the error checker and communicate the test sequence to the signal processing elements of a channel. One or more pull up resistors and/or termination resistors connect to the shared bus. The bus may comprise a clock signal path and a data signal path. The test sequence may be a pseudo-random bit sequence. The bus interface comprises an open collector current mode logic driver in cascode arrangement.

Abstract: Techniques for automatically determining an input resistance of an optical modulator and configuring a modulation current source can include applying a first bias current to an input of the optical transmitter and measuring a corresponding first voltage at the input of the optical transmitter. A second bias current can also be applied to the input of the optical transmitter and a corresponding second voltage at the input of the optical transmitter can be measured. An input resistance of the specific optical transmitter can be determined from the difference between the first and second voltages divided by the difference between the first and second bias currents. The technique can further include setting one or more configuration settings in one or more registers of a modulation current source based on the determined input resistance of the optical transmitter.

Abstract: Systems and methods for implementing a multimode splitting structure that divides a multimode wide waveguide into multiple narrower waveguides for photodetector connections in an optoelectronic system are disclosed. The optoelectronic system includes an optical filter, a multimode splitter, and a plurality of photodetector. The optical filter is communicatively coupled to a first waveguide to receive an optical signal and configured to demultiplex the optical signal onto a plurality of second waveguides based on different wavelengths. The multimode splitter is adapted to divide each of the plurality of second waveguides into a plurality of third waveguides. Each of the plurality of photodetector is adapted to be connected to each of the plurality of the third waveguide.

Abstract: An analog to digital converter temperature compensation system comprising a comparator configured to compare an analog input signal to a compensated feedback signal and generate a comparator output. A SAR module processes the comparator output to generate a digital signal. A digital to analog converter, biased by a biasing signal having temperature change induced error, is configured to convert the digital signal to a feedback signal and a detector is configured to detect a signal that is proportional to temperature. A look-up table is configured to receive and convert the signal that is proportional to temperature to a compensation signal such that the compensation signal compensates for the temperature change induced error in the biasing signal. A summing node combines the feedback signal with the compensation signal to create a compensated feedback signal.

Abstract: High power transistors, such as high power gallium nitride (GaN) transistors, are described. These high power transistors have larger total gate widths than conventional high power transistors by arranging multiple linear arrays of gate, drain, and source contacts in parallel. Thereby, the total gate width and the power rating of the high power transistor may be increased without elongating the die of the high power transistor. Accordingly, the die of the high power transistor may be mounted in a smaller circuit package relative to conventional dies with the same power rating.

Abstract: An optic reference signal generator comprising a housing forming an enclosed space with one or more air flow openings. Within the housing is an optic signal generator driver configured to generate an optic signal generator drive signal. An optic signal generator generates an optic signal responsive to the optic signal generator drive signal. A polarity control unit adjusts polarization of the optic signal to create a polarization adjusted optic signal and a modulator bias generator and controller generates a modulation signal. A pattern signal input receives a pattern signal and a modulator receives the polarization adjusted optic signal, the pattern signal, and the modulation signal to generate a modulated output signal.

Abstract: Semiconductor electro-optical modulators which receives an input optical signal and provides a modulated output optical signal based on an input electrical signal are disclosed. The semiconductor electro-optical modulator may comprise at least one electrical transmission line adapted to carry the input electrical signal and a semiconductor electro-optical phase shifter waveguide electrically coupled to the at least one electrical transmission line. An optical path length of the semiconductor electro-optical phase shifter waveguide between a modulation begin plane of the semiconductor electro-optical modulator and a modulation end plane of the semiconductor electro-optical modulator may be greater than an electrical path length of the electrical transmission line between the modulation begin plane of the semiconductor electro-optical modulator and the modulation end plane of the semiconductor electro-optical modulator.

Abstract: Vertical etch heterolithic integrated circuit devices are described. A method of manufacturing NIP diodes is described in one example. A P-type substrate is provided, and an intrinsic layer is formed on the P-type substrate. An oxide layer is formed on the intrinsic layer, and one or more openings are formed in the oxide layer. One or more N-type regions are implanted in the intrinsic layer through the openings in the oxide layer. The N-type regions form cathodes of the NIP diodes. A dielectric layer deposited over the oxide layer is selectively etched away with the oxide layer to expose certain ranges of the intrinsic layer to define a geometry of the NIP diodes. The intrinsic layer and the P-type substrate are vertically etched away within the ranges to expose sidewalls of the intrinsic layer and the P-type substrate. The P-type substrate forms the anodes of the NIP diodes.

Abstract: Disclosed are various embodiments for a pre-matched power resistance system including a pre-matching network for use with a passive electrical device, such as a Lange coupler or a Wilkinson power splitter, where the system provides a predetermined input impedance across a predetermined target bandwidth. The pre-matched power resistance system network further includes an on-chip thin film resistor disposed on a substrate comprising a plurality of coplanar sub-resistors electrically isolated from one another and a manifold portion comprising a plurality of manifold traces in a tiered arrangement terminating in an electrical connection to a respective one of the coplanar sub-resistors.

Abstract: The present invention facilitates optical modulation skew adjustment. Components of an on chip optical device driver system can cooperatively operate to provide modulated driver signals to drive configuration of optical signals. A serializer is configured to receive parallel data signals and forward corresponding serial data signals. A multiplexing component is configured to selectively output an in-phase component and a quadrature component of the serial data signals, including implementing skew adjustments to aspects of a first output signal and a second output signal. An output stage is configured to output signals that modulate an optical signal, including the first output signal and the second output signal. An on chip skew detector is configured to detect a skew difference between the first output signal and the second output signal. A skew calibration component is configured to direct skew adjustment between the first output signal and the second output signal.