Patent application number | Description | Published |
20090074019 | OPTICAL INJECTION LOCKING OF VCSELS FOR WAVELENGTH DIVISION MULTIPLEXED PASSIVE OPTICAL NETWORKS (WDM-PONS) - Low cost implementation of broadband upstream transmission for local and access network applications is made possible through the use of modulated downstream signals in a wavelength division multiplexed (WDM) passive optical network (PON) to injection-lock vertical-cavity surface-emitting lasers (VCSELs) for operation as stable, uncooled, and directly-modulated upstream transmitters. By way of example and not limitation, an optical network unit comprises: downstream input, photoreceiver, tunable laser, upstream output, and means for directionally coupling the downstream input into the tunable laser for modulating the output wavelength which is coupled to the upstream output. | 03-19-2009 |
20110146771 | NANONEEDLE PLASMONIC PHOTODETECTORS AND SOLAR CELLS - The present disclosure provides a catalyst-free growth mode of defect-free Gallium Arsenide (GaAs)-based nanoneedles on silicon (Si) substrates with a complementary metal-oxide-semiconductor (CMOS)-compatible growth temperature of around 400° C. Each nanoneedle has a sharp 2 to 5 nanometer (nm) tip, a 600 nm wide base and a 4 micrometer (μm) length. Thus, the disclosed nanoneedles are substantially hexagonal needle-like crystal structures that assume a 6° to 9° tapered shape. The 600 nm wide base allows the typical micro-fabrication processes, such as optical lithography, to be applied. Therefore, nanoneedles are an ideal platform for the integration of optoelectronic devices on Si substrates. A nanoneedle avalanche photodiode (APD) grown on silicon is presented in this disclosure as a device application example. The APD attains a high current gain of 265 with only 8V bias. | 06-23-2011 |
20110150502 | HIGH-SPEED OPTICAL TRANSMITTERS USING CASCADED OPTICALLY INJECTION-LOCKED LASERS - Apparatus and method for increasing optical transmission bandwidth in response to chaining, in cascade, one or more slave lasers onto a master laser. Each laser is configured for optical injection locking (OIL) and each slave laser is locked onto the master laser. The first and each subsequent slave laser are detuned to tailor frequency characteristics of apparatus output. The transmitter can be scaled up by cascading additional injection-locked lasers together. The invention supports multiple compatible modulation formats, such as amplitude modulation (AM), phase modulation (PM), and frequency modulation (FM), for tailoring the output to the application of interest, while any type of laser can be used for the master and slave lasers. | 06-23-2011 |
20110280269 | HIGH CONTRAST GRATING INTEGRATED VCSEL USING ION IMPLANTATION - A Vertical Cavity Surface Emitting Laser (VCSEL) and its fabrication are taught which incorporate a high contrast grating (HCG) to replace the top mirror of the device and which can operate at long-wavelengths, such as beyond 0.85 μm. The HCG beneficially provides a high degree of polarization differentiation and provides optical containment in response to lensing by the HCG. The device incorporates a quantum well active layer, a tunnel junction, and control of aperture width using ion implantation. A tunable VCSEL is taught which controls output wavelength in response to controlling a micro-mechanical actuator coupled to a HCG top mirror which can be moved to, or from, the body of the VCSEL. A fabrication process for the VCSEL includes patterning the HCG using a wet etching process, and highly anisotropic wet etching while precisely controlling temperature and PH. | 11-17-2011 |
20110280533 | ULTRA-LOW LOSS HOLLOW CORE WAVEGUIDE USING HIGH-CONTRAST GRATINGS - Optical waveguides using segmented periodically-spaced high contrast gratings bounding a hollow core propagation region on at least two sides. Incident light is received in a hollow waveguide (HW) region (core) between opposing HCG faces which provide lateral confinement in response to glancing reflections of the incident light beam from high refractive index segments of the HCG as it traverses the core. Embodiments are described for planar waveguides (1D) having a planar core between two planar HCGs, as well as | 11-17-2011 |
20120076161 | LONG DISTANCE TRANSMISSION USING MULTI-MODE VCSEL UNDER INJECTION LOCKING - Adjustable chirp is achieved in injection-locked, 10-Gb/s directly modulated, multimode 1.55-μm VCSELs for the first time, leading to 90× increase in standard single-mode fiber transmission distance to 90 km. | 03-29-2012 |
20120128019 | MONOLITHICALLY INTEGRATED MULTI-WAVELENGTH HIGH-CONTRAST GRATING VCSEL ARRAY - Multiple-wavelength VCSEL array apparatus and method having a high contrast grating (HCG) mirror which can be implemented on a single substrate in which only the dimensions of the HCG (e.g., duty cycle or the period) need be changed to alter the wavelength of a given VCSEL in response to changing the reflectivity phase of the HCG mirror. The HCG can be defined by any desired lithographic process. By using a broadband HCG mirror a large wavelength span over 100 nm is provided, such as covering the entire C-band. The HCG multi-wavelength VCSEL array enables single-transverse mode emission and polarization control and scalability with respect to wavelength. | 05-24-2012 |
20130051419 | HCG REFLECTION ENHANCEMENT IN DIVERSE REFRACTIVE INDEX MATERIAL - Enhanced reflectivity High-Contrast Gratings are described which operate in different medium. An HCG is described with a deep/buried metallization layer separated at a distance of least three to four grating thicknesses from the grating. Reflective bandwidth of the HCG is substantially increased, such as by a factor or five, by inclusion of the deep/buried metallization layer. An HCG is described which provides high reflectivity, even when embedded into materials of a moderate to high index of refraction, such as semiconductor material. Vertical cavity surface emitting laser embodiments are described which utilize these reflectivity enhancements, and preferably utilize HCG reflectors for top and/or bottom mirrors. | 02-28-2013 |
20130058370 | PLANAR, HIGH NA, LOW LOSS TRANSMITTING OR REFLECTING LENSES USING SUB-WAVELENGTH HIGH CONTRAST GRATING - Planar lenses and reflectors are described comprising subwavelength high-contrast gratings (HCG) having high index of refraction grating elements spaced apart from one another in straight and/or curved segments and surrounded by low index material. The high-contrast grating is configured to receive an incident wave which excites multiple modes within the high-contrast grating and is focused for reflection and/or transmission by said high contrast grating. The width of the high contrast grating bars vary along a distribution direction of the grating bars which is perpendicular to the length of the grating bars and/or varies along the length of one or more grating bars to focus said reflection and/or transmission. The HCG is configured to provide double focusing, whose use is exemplified within a vertical cavity surface emitting laser (VCSEL) structure using focusing HCG structures for both the top and bottom mirrors. | 03-07-2013 |
20130330875 | NANONEEDLE PLASMONIC PHOTODETECTORS AND SOLAR CELLS - The present disclosure provides a method for a catalyst-free growth mode of defect-free Gallium Arsenide (GaAs)-based nanoneedles on silicon (Si) substrates with a complementary metal-oxide-semiconductor (CMOS)-compatible growth temperature of around 400° C. Each nanoneedle has a sharp 2 to 5 nanometer (nm) tip, a 600 nm wide base and a 4 micrometer (μm) length. Thus, the disclosed nanoneedles are substantially hexagonal needle-like crystal structures that assume a 6° to 9° tapered shape. The 600 nm wide base allows the typical micro-fabrication processes, such as optical lithography, to be applied. Therefore, nanoneedles are an ideal platform for the integration of optoelectronic devices on Si substrates. A nanoneedle avalanche photodiode (APD) grown on silicon is presented in this disclosure as a device application example. The APD attains a high current gain of 265 with only 8V bias. | 12-12-2013 |
20140353530 | POLARIZATION INDEPENDENT DUAL USAGE HCG VCSEL-DETECTOR WITH HIGH CONTRAST GRATING AND TWO DIMENSIONAL PERIOD STRUCTURE - A dual usage HCG VCSEL detector is provided with a high contrast grating (HCG) reflector first reflector that has a two dimensional periodic structure. The two dimensional structure is a periodic structure that is a symmetric structure with periodic repeating. The symmetrical structure provides that polarization modes of light are undistinguishable. A second reflector is in an opposing relationship to the first reflector. A tunable optical cavity is between the first and second reflectors. An active region is positioned in the cavity between the first and second reflectors. The photodetector is polarization independent. An MQW light absorber is included converts light to electrons. A dual usage HCG VCSEL-detector includes a high contrast grating (HCG) reflector first reflector, and a second reflector in an opposing relationship to the first reflector. A tunable optical cavity is between the first and second reflectors. An active region is positioned in the cavity between the first and second reflectors. The dual usage HCG VCSEL-detector that operates as a dual usage HCG VCSEL and as a tunable photodetector. | 12-04-2014 |
20140353583 | POLARIZATION INDEPENDENT PHOTODETECTOR WITH HIGH CONTRAST GRATING AND TWO DIMENSIONAL PERIOD STRUCTURE - A photodetector is provided with a high contrast grating (HCG) reflector first reflector that has a two dimensional periodic structure. The two dimensional structure is a periodic structure that is a symmetric structure with periodic repeating. The symmetrical structure provides that polarization modes of light are undistinguishable. A second reflector is in an opposing relationship to the first reflector. A tunable optical cavity is between the first and second reflectors. An active region is positioned in the cavity between the first and second reflectors. The photodetector is polarization independent. An MQW light absorber is included converts light to electrons. | 12-04-2014 |
20140353712 | NANOPILLAR OPTICAL RESONATOR - Embodiments of a monolithically integrated optical resonator are disclosed. In one embodiment, the optical resonator is a nanopillar optical resonator that is formed directly on a substrate and promotes a helically-propagating cavity mode. The helically-propagating cavity mode results in significant reflection or, in some embodiments, total internal reflection at an interface of the nanopillar optical resonator and the substrate even if refractive indices of the nanopillar optical resonator and the substrate are the same or similar. As a result, strong optical feedback, and thus strong resonance, is provided in the nanopillar optical resonator. | 12-04-2014 |