Abstract: A semiconductor gas imaging device system and method includes one chip dual band Type II Superlattice (T2SL) detectors comprising two back to back diodes wherein the bias is flipped. Embodiment voltages are +1V to ?1V. For embodiments, only the detector with negative voltage detects incoming infrared radiation.

Abstract: A semiconductor gas imaging device system and method includes one chip dual band Type II Superlattice (T2SL) detectors comprising two back to back diodes wherein the bias is flipped. Embodiment voltages are +1V to ?1V. For embodiments, only the detector with negative voltage detects incoming infrared radiation.

Abstract: Pixels in a focal plane array are defined by controlled variation of the Fermi energy at the surface of the detector array. Varying the chemical composition of the semiconductor at the detector surface produces a corresponding variation in the surface Fermi energy which produces a corresponding variation in the electric field and electrostatic potential in the bulk semiconductor below the surface. This defines pixels by having one Fermi energy at the surface of each pixel and a different Fermi energy at the surface between pixels. Fermi energy modulation can also be controlled by applying an electrostatic potential voltage V1 to the metal pad defining each pixel, and applying a different electrostatic potential voltage V2 to an interconnected metal grid covering the gaps between all the pixel metal pads. Methods obviate the need to etch deep trenches between pixels, resulting in a more manufacturable quasi-planar process without sacrificing performance.

Abstract: Pixels in a focal plane array are defined by controlled variation of the Fermi energy at the surface of the detector array. Varying the chemical composition of the semiconductor at the detector surface produces a corresponding variation in the surface Fermi energy which produces a corresponding variation in the electric field and electrostatic potential in the bulk semiconductor below the surface. This defines pixels by having one Fermi energy at the surface of each pixel and a different Fermi energy at the surface between pixels. Fermi energy modulation can also be controlled by applying an electrostatic potential voltage V1 to the metal pad defining each pixel, and applying a different electrostatic potential voltage V2 to an interconnected metal grid covering the gaps between all the pixel metal pads. Methods obviate the need to etch deep trenches between pixels, resulting in a more manufacturable quasi-planar process without sacrificing performance.

Abstract: A QWIP structure is disclosed that includes a graded emitter barrier and can further be configured with a blocked superlattice miniband. The graded emitter barrier effectively operates to launch dark electrons into the active quantum well region, thereby improving responsivity. A graded collector barrier may also be included for reverse bias applications. The configuration operates to eliminate or otherwise reduce image artifacts or persistence associated with dielectric relaxation effect in low-background applications.

Abstract: A tunable QWIP FPA device that is configured for spectral tunability for performing the likes of imaging and spectroscopy is disclosed. A selected bias voltage is applied across the contacts associated with a particular detector layer/channel of the device, where each applied bias corresponds to a particular target spectrum/color for detection. Each detector layer/channel can be coarse tuned for a bimodal or dual-band operation (e.g., MWIR/LWIR). Also, each detector layer/channel is configured for continuous or fine tuning within a particular mode (e.g., MWIR/MWIR). Thus, dynamic bias-controlled tuning is enabled. Asymmetric quantum well configurations enable this tunability.

Abstract: A QWIP structure is disclosed that is configured with enhanced optical coupling to improve absorption capability and efficiency. A waffle-type light-coupling grating having a pattern of etched wells operates to improve absorption by preventing photons from bouncing out of the detector sensing areas. A post-type light coupling grating can also be used. Parameters of the grating, including its orientation, pitch, and etch depth, can be adjusted to optimize specific color detection. The grating can include a hybrid metal layer including both ohmic and reflective qualities to further improve quantum and conversion efficiency. A “photon-in-a-box” configuration is also disclosed, where sides of the QWIP sensing areas are coated with reflective metal to further inhibit the escaping of photons. The material design and number of quantum wells per QWIP can be selected so as to exploit the avalanche effect, thereby increasing device responsivity.

Abstract: A QWIP structure is disclosed that includes a graded emitter barrier and can further be configured with a blocked superlattice miniband. The graded emitter barrier effectively operates to launch dark electrons into the active quantum well region, thereby improving responsivity. A graded collector barrier may also be included for reverse bias applications. The configuration operates to eliminate or otherwise reduce image artifacts or persistence associated with dielectric relaxation effect in low-background applications.

Abstract: A QWIP structure is disclosed that includes a graded emitter barrier and can further be configured with a blocked superlattice miniband. The graded emitter barrier effectively operates to launch dark electrons into the active quantum well region, thereby improving responsivity. A graded collector barrier may also be included for reverse bias applications. The configuration operates to eliminate or otherwise reduce image artifacts or persistence associated with dielectric relaxation effect in low-background applications.

Abstract: A multi-wavelength optical communication system includes a number of emitters each of which emits radiation at a different wavelength; a plurality of the detectors each of which senses radiation at a different wavelength corresponding to the radiation from one of the emitters and a shared waveguide including a scattering medium to transmit emitted radiation to the detectors.

Abstract: A multi-wavelength optical communication system includes a number of emitters each of which emits radiation at a different wavelength; a plurality of the detectors each of which senses radiation at a different wavelength corresponding to the radiation from one of the emitters and a shared waveguide including a scattering medium to transmit emitted radiation to the detectors.

Abstract: The present invention relates to an optical modulator array that uses stepped-well continuously tunable quantum well infrared modulators in order to accomplish electronic beam modulating. The present invention involves a coherent optical beam modulating device to steer an optical beam comprising: an optical modulator array, where said optical modulator array includes a stepped quantum well doped with electrons, wherein the modulator array affects operates as at least one of a phase modulator and a light intensity modulator base upon a voltage bias applied across the modulator array. The continuous tunable quantum well modulator includes asymmetry of the unit cell that allows transitions from the ground state to the second excited state that are normally forbidden in symmetrical quantum well infrared photodetectors.

Abstract: A QWIP structure is disclosed that includes a graded emitter barrier and can further be configured with a blocked superlattice miniband. The graded emitter barrier effectively operates to launch dark electrons into the active quantum well region, thereby improving responsivity. A graded collector barrier may also be included for reverse bias applications. The configuration operates to eliminate or otherwise reduce image artifacts or persistence associated with dielectric relaxation effect in low-background applications.

Abstract: A semiconductor-based, photo detector device capable of simultaneously detecting two or more selected wavelengths of light on a pixel-registered basis. The device has detector layers of selected semiconductor materials of one micron or less in thickness interspersed with contact layers, each detector layer having a different light absorption to wavelength response curve. All contact layers, including detector bias voltages, have electrical contacts on the backside of the pixel for discrete pixel connection to mating connections on a suitable ROIC substrate. Among its several embodiments, there is a multi-color detector array and a single channel per pixel differential optical signal detector.

Abstract: A tunable QWIP FPA device that is configured for spectral tunability for performing the likes of imaging and spectroscopy is disclosed. A selected bias voltage is applied across the contacts associated with a particular detector layer/channel of the device, where each applied bias corresponds to a particular target spectrum/color for detection. Each detector layer/channel can be coarse tuned for a bimodal or dual-band operation (e.g., MWIR/LWIR). Also, each detector layer/channel is configured for continuous or fine tuning within a particular mode (e.g., MWIR/MWIR). Thus, dynamic bias-controlled tuning is enabled. Asymmetric quantum well configurations enable this tunability.

Abstract: A QWIP structure is disclosed that is configured with enhanced optical coupling to improve absorption capability and efficiency. A waffle-type light-coupling grating having a pattern of etched holes operates to improve absorption by preventing photons from bouncing out of the detector sensing areas. A post-type light coupling grating can also be used. Parameters of the grating, including its orientation, pitch, and etch depth, can be adjusted to optimize specific color detection. The grating can include a hybrid metal layer including both ohmic and reflective qualities to further improve quantum and conversion efficiency. A “photon-in-a-box” configuration is also disclosed, where sides of the QWIP sensing areas are coated with reflective metal to further inhibit the escaping of photons. The material design and number of quantum wells per QWIP can be selected so as to exploit the avalanche effect, thereby increasing device responsivity.

Abstract: A system to facilitate alignment of an optical connector to respective optical channels of one or more optical arrays. Optical planar arrays having multiple optical emitters and multiple optical detectors of a multi-channel optical link are aligned by employing supporting circuitry and software that controls the optical devices, enabling all receivers, turning on the transmitters sequentially, and recording the optimal transmitter/receiver pairs. Another feature of the invention is the aspect of redundancy, wherein the system establishes a record of spare emitters and spare detectors that are used when the selected transmitter receiver pair degrades or fails. The techniques of the present invention also provide a unique multiplexer/demultiplexer arrangement for a single wavelength channel of emitters and detectors.

Abstract: The present invention relates to an optical modulator array that uses stepped-well continuously tunable quantum well infrared modulators in order to accomplish electronic beam modulating. The present invention involves a coherent optical beam modulating device to steer an optical beam comprising: an optical modulator array, where said optical modulator array includes a stepped quantum well doped with electrons, wherein the modulator array affects operates as at least one of a phase modulator and a light intensity modulator base upon a voltage bias applied across the modulator array. The continuous tunable quantum well modulator includes asymmetry of the unit cell that allows transitions from the ground state to the second excited state that are normally forbidden in symmetrical quantum well infrared photodetectors.

Abstract: An AlxGa1−xAs/GaAs/AlxGa1−xAs quantum well exhibiting a bound-to-quasibound intersubband absorptive transition is described. The bound-to-quasibound transition exists when the first excited state has the same energy as the “top” (i.e., the upper-most energy barrier) of the quantum well. The energy barrier for thermionic emission is thus equal to the energy required for intersubband absorption. Increasing the energy barrier in this way reduces dark current. The amount of photocurrent generated by the quantum well is maintained at a high level.

Abstract: An array of devices for electronically steering a laser beam. A plurality of quantum well absorption modulators steer a laser beam, either reflective or transmissive, without moving parts and operable at room temperature. The foregoing is accomplished using intraband, also termed intersubband, transitions in the quantum wells.