Abstract: A heterostructure for an optoelectronic device is disclosed. The heterostructure includes an active region including at least one quantum well and at least one barrier and an electron blocking layer located adjacent to the active region, wherein the electron blocking layer includes a region of graded composition. An asymmetric p-type superlattice layer is located adjacent to the electron blocking layer, wherein the p-type superlattice includes at least one superlattice period comprising a set of wells and a set of barriers. A thickness of at least one of: each well in the set of wells or each barrier in the set of barriers varies along a length of the p-type superlattice.

Abstract: A diffusive layer including a laminate of a plurality of transparent films is provided. At least one of the plurality of transparent films includes a plurality of diffusive elements with a concentration that is less than a percolation threshold. The plurality of diffusive elements are optical elements that diffuse light that is impinging on such element. The plurality of diffusive elements can be diffusively reflective, diffusively transmitting or combination of both. The plurality of diffusive elements can include fibers, grains, domains, and/or the like. The at least one film can also include a powder material for improving the diffusive emission of radiation and a plurality of particles that are fluorescent when exposed to radiation.

Abstract: An improved heterostructure for an optoelectronic device is provided. The heterostructure includes an active region, an electron blocking layer, and a p-type contact layer. The p-type contact layer and electron blocking layer can be doped with a p-type dopant. The dopant concentration for the electron blocking layer can be at most ten percent the dopant concentration of the p-type contact layer. A method of designing such a heterostructure is also described.

Abstract: An optoelectronic device configured for improved light extraction through a region of the device other than the substrate is described. A group III nitride semiconductor layer of a first polarity is located on the substrate and an active region can be located on the group III nitride semiconductor layer. A group III nitride semiconductor layer of a second polarity, different from the first polarity, can located adjacent to the active region. A first contact can directly contact the group III nitride semiconductor layer of the first polarity and a second contact can directly contact the group III nitride semiconductor layer of the second polarity. Each of the first and second contacts can include a plurality of openings extending entirely there through and the first and second contacts can form a photonic crystal structure. Some or all of the group III nitride semiconductor layers can be located in nanostructures.

Abstract: A solution for treating a fluid, such as water, is provided. An ultraviolet transparency of a fluid can be determined before or as the fluid enters a disinfection chamber. In the disinfection chamber, the fluid can be irradiated by ultraviolet radiation to harm microorganisms that may be present in the fluid. One or more attributes of the disinfection chamber, fluid flow, and/or ultraviolet radiation can be adjusted based on the transparency to provide more efficient irradiation and/or higher disinfection rates. In addition, various attributes of the disinfection chamber, such as the position of the inlet(s) and outlet(s), the shape of the disinfection chamber, and other attributes of the disinfection chamber can be utilized to create a turbulent flow of the fluid within the disinfection chamber to promote mixing and improve uniform ultraviolet exposure.

Abstract: An approach for providing illumination with a blue UV light source, which can be used in combination with a visible light source is disclosed. In operation, the visible light source emits visible light at a first intensity. The blue UV light source emits blue UV light at a second intensity. The blue UV light stimulates fluorescence from a surface of an object illuminated by the blue UV light. A sensor can detect the intensity of the fluorescence from the surface illuminated by the blue UV light source. A control module can be operatively coupled to the visible light source, the blue UV light source, and the at least one sensor, and be configured to change the intensity of the visible light and/or the intensity of the blue UV light as a function of the fluorescent intensity detected by the sensor.

Abstract: Fabrication of a heterostructure, such as a group III nitride heterostructure, for use in an optoelectronic device is described. The heterostructure can be epitaxially grown on a sacrificial layer, which is located on a substrate structure. The sacrificial layer can be at least partially decomposed using a laser. The substrate structure can be completely removed from the heterostructure or remain attached thereto. One or more additional solutions for detaching the substrate structure from the heterostructure can be utilized. The heterostructure can undergo additional processing to form the optoelectronic device.

Abstract: An illuminator comprising more than one set of ultraviolet radiation sources. A first set of ultraviolet radiation sources operate in a wavelength range of approximately 270 nanometers to approximately 290 nanometers. A second set of ultraviolet radiation sources operate in a wavelength range of approximately 380 nanometers to approximately 420 nanometers. The illuminator can also include a set of sensors for acquiring data regarding at least one object to be irradiated by the first and the second set of ultraviolet radiation sources. A control system configured to control and adjust a set of radiation settings for the first and the second set of ultraviolet radiation sources based on the data acquired by the set of sensors.

Abstract: A system for providing ultraviolet treatment of volatile organic compounds (VOCs) is disclosed. The system can include a first gas conduit to carry a stream of gas having VOCs and a second gas conduit to carry a second stream of gas containing a partial pressure of water vapor. A gas treatment unit can be coupled to the first gas conduit and the second gas conduit. The gas treatment unit can form hydroxyl radicals from the water vapor in the stream of gas carried by the second gas conduit and inject the radicals in the first gas conduit to decrease the presence of the VOCs. The gas treatment unit can include a photocatalyst component and at least one ultraviolet radiation source to irradiate the photocatalyst component with ultraviolet radiation. To this extent, the irradiated photocatalyst component disassociates the gas containing the water vapor to form the hydroxyl radicals.

Abstract: A solution for treating a fluid, such as water, is provided. An ultraviolet transparency of a fluid can be determined before or as the fluid enters a disinfection chamber. In the disinfection chamber, the fluid can be irradiated by ultraviolet radiation to harm microorganisms that may be present in the fluid. One or more attributes of the disinfection chamber, fluid flow, and/or ultraviolet radiation can be adjusted based on the transparency to provide more efficient irradiation and/or higher disinfection rates. In addition, various attributes of the disinfection chamber, such as the position of the inlet(s) and outlet(s), the shape of the disinfection chamber, and other attributes of the disinfection chamber can be utilized to create a turbulent flow of the fluid within the disinfection chamber to promote mixing and improve uniform ultraviolet exposure.

Abstract: Ultraviolet irradiation of an aquatic environment for the purposes of sterilization, disinfection, and/or cleaning fluids and surfaces associated with the aquatic environment. The aquatic environment can be irradiated using an ultraviolet illuminator having at least one ultraviolet radiation source and at least one sensor to detect conditions of the aquatic environment including fluid conditions and/or surface conditions associated with the aquatic environment. A control unit, operatively coupled to the at least one ultraviolet radiation source and the at least one sensor, determines a presence of algae growth about the aquatic environment. The control unit is further configured to direct the at least one ultraviolet radiation source to irradiate the aquatic environment at locations where there is a presence of algae growth for removal and suppression of further growth, monitor the irradiation with the at least one sensor, and adjust irradiation parameters as a function of detected conditions.

Abstract: A diffusive layer including a laminate of a plurality of transparent films is provided. At least one of the plurality of transparent films includes a plurality of diffusive elements with a concentration that is less than a percolation threshold. The plurality of diffusive elements are optical elements that diffuse light that is impinging on such element. The plurality of diffusive elements can be diffusively reflective, diffusively transmitting or combination of both. The plurality of diffusive elements can include fibers, grains, domains, and/or the like. The at least one film can also include a powder material for improving the diffusive emission of radiation and a plurality of particles that are fluorescent when exposed to radiation.

Abstract: An optoelectronic device with a multi-layer contact is described. The optoelectronic device can include an n-type semiconductor layer having a surface. A mesa can be located over a first portion of the surface of the n-type semiconductor layer and have a mesa boundary, which has a shape including a plurality of interconnected fingers. The n-type semiconductor layer can have a shape at least partially defined by the mesa boundary. A first n-type contact layer can be located adjacent to another portion of the n-type semiconductor contact layer, where the first n-type contact layer forms an ohmic contact with the n-type semiconductor layer. A second contact layer can be located over a second portion of the n-type semiconductor contact layer, where the second contact layer is formed of a reflective material.

Abstract: A wearable fluorescent article of adornment with ultraviolet radiation source of excitation is described. At least one ultraviolet light emitting source can irradiate a fluorescent material with ultraviolet radiation. The fluorescent material can generate fluorescent light in response to excitation of the fluorescent material with ultraviolet radiation emitted from the at least one ultraviolet light emitting source. The article of adornment can transmit the fluorescent light generated from the fluorescent material while absorbing the ultraviolet radiation. A control unit can control irradiation of the fluorescent material with the at least one ultraviolet light emitting source, while a power supply component can power the at least one ultraviolet light emitting source and/or the control unit.

Abstract: Ultraviolet radiation is directed within an area. The storage area is scanned and monitored for the presence of biological activity within designated zones. Once biological activity is identified, ultraviolet radiation is directed to sterilize and disinfect designated zones within the storage area.

Abstract: A heterostructure for use in an electronic or optoelectronic device is provided. The heterostructure includes one or more semiconductor layers containing columnar nanostructures (e.g., nanowires). The nanowire semiconductor layer can include sub-layers of varying composition, at least one of which is an active layer that can include quantum wells and barriers. A heterostructure can include n-type and p-type semiconductor contact layers adjacent to the nanowire semiconductor layer containing the active layer.

Abstract: An ultraviolet razor blade treatment system for providing a cleaning treatment to a shaving razor is disclosed. The ultraviolet razor blade treatment system can include a shaving razor cleaning unit that has at least one ultraviolet radiation source and sensor to clean surfaces of the shaving razor for purposes of disinfection, sterilization, and/or sanitization.

Abstract: An illuminator comprising more than one set of ultraviolet radiation sources. A first set of ultraviolet radiation sources operate in a wavelength range of approximately 270 nanometers to approximately 290 nanometers. A second set of ultraviolet radiation sources operate in a wavelength range of approximately 380 nanometers to approximately 420 nanometers. The illuminator can also include a set of sensors for acquiring data regarding at least one object to be irradiated by the first and the second set of ultraviolet radiation sources. A control system configured to control and adjust a set of radiation settings for the first and the second set of ultraviolet radiation sources based on the data acquired by the set of sensors.

Abstract: Medical devices capable of delivering and/or sensing electromagnetic radiation within an organism body are described. Placement of a location for delivering and/or sending the electromagnetic radiation is done through the skin of the organism body. Devices described include a needle with a wave guiding structure configured to direct the electromagnetic radiation to/from a location within the organism body.

Abstract: Ultraviolet radiation is directed within an area. Items located within the area and/or one or more conditions of the area are monitored over a period of time. Based on the monitoring, ultraviolet radiation sources are controlled by adjusting a direction, an intensity, a pattern, and/or a spectral power of the ultraviolet radiation generated by the ultraviolet radiation source. Adjustments to the ultraviolet radiation source(s) can correspond to one of a plurality of selectable operating configurations including a storage life preservation operating configuration, a disinfection operating configuration, and an ethylene decomposition operating configuration.