Abstract: A method of forming a solder connection includes forming a solder mask on a thermal pad of a printed circuit board. The solder mask leaves unmasked portions of the thermal pad and forming the solder mask includes forming a plurality of mask stripes extending from edges of each unmasked portion towards a center of the unmasked portion. The method includes depositing solder paste on the unmasked portions of the thermal pad and placing an exposed thermal pad of an integrated circuit package on the solder paste deposited on the thermal pad of the printed circuit board. The method includes forming a solder connection by heating the solder paste between the unmasked portions of the thermal pad on the printed circuit board and the exposed thermal pad of the integrated circuit package.

Abstract: A method, apparatus, and system for forming a semiconductor structure. A first oxide layer located on a set of group III nitride layers formed on a silicon carbide substrate is bonded to a second oxide layer located on a carrier substrate to form an oxide layer located between the carrier substrate and the set of group III nitride layers. The silicon carbide substrate has a doped layer. The silicon carbide substrate having the doped layer is etched using a photo-electrochemical etching process, wherein a doping level of the doped layer is such that the doped layer is removed and a silicon carbide layer in the silicon carbide substrate remains unetched. The semiconductor structure is formed using the silicon carbide layer and the set of group III nitride layers.

Abstract: A semiconductor structure comprises a substrate; an oxide layer on the substrate; a set of group III nitride layers on the oxide layer; and a set of silicon carbide layers located on the set of group III nitride layers.

Abstract: Systems, methods, and devices are disclosed for implementing photonic links. Methods include transmitting light using an optical emitter, splitting, using an input coupler, the light into a first path and a second path, the first path being provided to a modulator, and the second path being provided to a phase shifter, and combining, using an output coupler, an output of the modulator and an output of the phase shifter. Methods further include identifying a modulator phase angle that reduces a third order distortion at an output of the output coupler, applying a first bias voltage to a modulator to maintain the identified modulator phase angle, and applying a control signal to the phase shifter to maintain a phase difference between an output of the modulator and an output of a phase shifter.

Abstract: The invention is a Demodulator for an Optical Analog Pulse Position Modulated signal suitable for inclusion in receivers for Free Space Optical communication systems. In one embodiment the Demodulator may use the pulse position modulated optical information signal and the clock signal with different wavelengths. By proper biasing of a Semiconductor Optical Amplifier and selection of wavelengths for the information signal and the clock signal, the performance of the Demodulator is made insensitive to noise in the received signals.

Abstract: An optical transmitter includes a superconducting driver circuit including at least one Josephson junction, the superconducting driver circuit having a voltage output and having a connection to a circuit ground, a first bias circuit coupled to the voltage output of the superconducting driver circuit, a second bias circuit, wherein the second bias circuit establishes a positive bias voltage relative to the circuit ground, and an electro-optic device having a first end and a second end, wherein the first end of the electro-optic device is coupled to the voltage output of the superconducting driver circuit, and wherein the second end of the electro-optic device is coupled to the second bias circuit.

Abstract: A laser or light emitter for operation at a cryogenic temperature includes a single quantum well layer, an n-type barrier layer directly on a first surface of the single quantum well layer, and a p-type barrier layer directly on a second surface of the single quantum well layer opposite the first surface of the single quantum well layer. The single quantum well layer is between the p-type barrier layer and the n-type barrier layer and the compositions of the n-type barrier layer and the p-type barrier layer are graded.

Abstract: An infrared photo-detector and a method for manufacturing it are disclosed. The infrared photo-detector contains a collector region, a first absorber layer absorbing a first wavelength band of incident light, wherein the first absorber layer is disposed between the collector region and the incident light, a second absorber layer absorbing a second wavelength band of light, wherein the first absorber layer is disposed between the second absorber layer and the incident light, at least one first electrical contact coupled with the first absorber layer, at least one second electrical contact coupled with the second absorber layer and at least one third electrical contact coupled with the collector, wherein the at least one third electrical contact provides a current associated with absorbed light of the first wavelength band and absorbed light of the second wavelength band. The method disclosed teaches how to manufacture the infrared photo-detector.

Abstract: An optical imager comprising an input lens system, a non-linear optic crystal, a pump source, and a photodetector array; the input lens system coupling input or incident light onto the non-linear optic crystal, the pump source providing pump light for the non-linear optical crystal, the non-linear optical crystal producing output light from a combination of the input light and the pump light, and the photodetector array detecting the output light produced by the non-linear optic crystal. The non-linear optic crystal preferably has a waveguided structure. The non-linear optic crystal has an optical cavity which is preferably shared with optical cavities of a plurality of lasers generating the pump light.

Abstract: A laser or light emitter for operation at a cryogenic temperature includes a single quantum well layer, an n-type barrier layer directly on a first surface of the single quantum well layer, and a p-type barrier layer directly on a second surface of the single quantum well layer opposite the first surface of the single quantum well layer. The single quantum well layer is between the p-type barrier layer and the n-type barrier layer and the compositions of the n-type barrier layer and the p-type barrier layer are graded.

Abstract: A gas-phase chemical analyzer has at least one gas chromatography column in gas-flow communication with at least one gas carrying tube of an optical absorption cell, a laser for illuminating molecules in a gas mixture flowing though the at least one gas carrying tube of the optical absorption cell, and a photodetector or photodetecting apparatus for measuring absorption spectra of the gas mixture illuminated by the laser. A first module is provided for statically identifying particular molecules in the gas mixture from other molecules in said gas mixture and a second module is provided for comparing at least selected ones of the particular molecules in the gas mixture with a reference library of absorption spectra of previously identified molecules and for determining the likelihood of a correct identification of the particular molecules in the gas mixture and the previously identified molecules in the reference library.

Abstract: A phased array that comprises a predetermined number of emitter/receiver elements; said emitter/receiver elements being arranged on a array formed of stacked rows, wherein the emitter/receiver elements in each row of the array are distributed according to a pseudo-random pattern; and the heights of the rows vary according to a pseudo-random pattern.

Abstract: A method of forming a solder connection includes forming a solder mask on a thermal pad of a printed circuit board. The solder mask leaves unmasked portions of the thermal pad and forming the solder mask includes forming a plurality of mask stripes extending from edges of each unmasked portion towards a center of the unmasked portion. The method includes depositing solder paste on the unmasked portions of the thermal pad and placing an exposed thermal pad of an integrated circuit package on the solder paste deposited on the thermal pad of the printed circuit board. The method includes forming a solder connection by heating the solder paste between the unmasked portions of the thermal pad on the printed circuit board and the exposed thermal pad of the integrated circuit package.

Abstract: A photonic modulator includes a first electro-optical waveguide, the first electro-optical waveguide having a first electro-optical waveguide side and a second electro-optical waveguide side opposite the first electro-optical waveguide side, a second electro-optical waveguide, the second electro-optical waveguide having a third electro-optical waveguide side and a fourth electro-optical waveguide side opposite the third electro-optical waveguide side, a first driven radio frequency electrode coupled to the first electro-optical waveguide side, a second driven radio frequency electrode coupled to the third electro-optical waveguide side, and a floating electrode coupled to the second electro-optical waveguide side and coupled to the fourth electro-optical waveguide side. The second electro-optical waveguide side and the third electro-optical waveguide side face each other and are spaced apart from one another.

Abstract: A radio frequency (RF) link includes a link transmitter that includes a data modulator for modulating a data waveform together with an RF carrier, a photonic encoder coupled to the data modulator, and a transmitter antenna for transmitting an RF signal, wherein the RF signal comprises an output of the photonic encoder, and a link receiver including a receiver antenna for receiving the RF signal, a first laser source, a photonic limiter coupled to the first laser source and to the receiving antenna, a photonic decoder coupled to the photonic limiter, a photo-receiver coupled to the photonic decoder, and a demodulator coupled to the photo-receiver for demodulating an output of the photo-receiver with the RF carrier to form a data output.

Abstract: A photonic waveguide for conducting light having first and second wavelengths, the waveguide comprising superposed first and second strips of light conducting semiconductor materials having first and second refractive indexes, wherein the second wavelength is shorter than the first wavelength and the second refractive index is higher than the first refractive index, wherein the width and height of the first strip of light conducting semiconductor material are such that the first strip of light conducting semiconductor material is adapted to confine an optical mode of the first wavelength and the width and height of the second strip of light conducting semiconductor material are such that the second strip of light conducting semiconductor material is adapted to confine an optical mode of the second wavelength but is too narrow to confine an optical mode of the first wavelength.

Abstract: A sensor system including a spectrometer with a light source having a plurality of selectable wavelengths, a controller for controlling the sensor system, for selecting wavelengths of illumination light produced by the light source, and for controlling the light source to illuminate a spatial location, a photodetector aligned to detect light received from the spatial location, a blind demixer coupled to the photodetector for separating received spectra in the detected light into a set of sample spectra associated with different demixed or partially demixed chemical components, a memory having a plurality of stored reference spectra, a non-blind demixer coupled to the blind demixer and to the memory for non-blind demixing of the sample spectra using the reference spectra, and a classifier coupled to the non-blind demixer for classifying the set of demixed sample spectra into chemical components using the reference spectra.

Abstract: A position sensitive detector includes a substrate, an absorber layer on the substrate, a barrier layer on the absorber layer, a contact layer on the barrier layer, and a first contact and a second contact on the contact layer. The barrier layer prevents a flow of majority carriers from the absorber layer to the contact layer. The position sensitive detector is sensitive to a lateral position between the first contact and the second contact of incident light on the contact layer.

Abstract: An electro-optic modulation structure comprises a first electrode and a second electrode and a first electro-optic strip; wherein the first electrode has a slab portion and a first ridge protruding from the slab portion of the first electrode, and the second electrode has a slab portion and a first ridge protruding from the slab portion of the second electrode, the first protruding ridge of the first electrode and the first protruding ridge of the second electrode being disposed on opposite sides of the first electro-optic strip and both protruding ridges abut the first electro-optic strip.

Abstract: Described in this disclosure is a space-variant Multi-domain Foveated Compressive Sensing (MFCS) system for adaptive imaging with variable resolution in spatial, polarization, and spectral domains simultaneously and with very low latency between multiple adaptable regions of interest (ROIs) across the field of view (FOV). The MFCS system combines space-variant foveated compressive sensing (FCS) imaging covered by a previous disclosure with a unique dual-path high efficiency optical architecture for parallel multi-domain compressive sensing (CS) processing. A single programmable Digital Micromirror Device (DMD) micro-mirror array is used at the input aperture to adaptively define and vary the resolution of multiple variable-sized ROIs across the FOV, encode the light for CS reconstruction, and adaptively divide the input light among multiple optical paths using complementary measurement codes, which can then be reconstructed as desired.