Abstract: Frontside-illuminated barrier infrared photodetector devices and methods of fabrication are disclosed. In one embodiment, a frontside-illuminated barrier infrared photodetector includes a transparent carrier substrate, and a plurality of pixels. Each pixel of the plurality of pixels includes an absorber layer, a barrier layer on the absorber layer, a collector layer on the barrier layer, and a backside electrical contact coupled to the absorber layer. Each pixel has a frontside and a backside. The absorber layer and the barrier layer are non-continuous across the plurality of pixels, and the barrier layer of each pixel is closer to a scene than the absorber layer of each pixel. A plurality of frontside common electrical contacts is coupled to the frontside of the plurality of pixels, wherein the frontside of the plurality of pixels and the plurality of frontside common electrical contacts are bonded to the transparent carrier substrate.

Abstract: An optical semiconductor device includes a lower electrode layer formed over a semiconductor substrate, an infrared absorption layer formed over the lower electrode layer 26, and an upper electrode layer 38 formed over the infrared absorption layer 36. The infrared absorption layer includes a quantum dot having dimensions different among directions stacked, and is sensitive to infrared radiation of wavelengths different corresponding to polarization directions.

Abstract: Consistent with the present disclosure, a package is provided that includes a housing having a recessed portion to accommodate an integrated circuit or chip. The housing has an inner periphery that defines or delineates the recessed portion. The inner periphery may be stepped and includes first and second surfaces that are spaced vertically from one another and extend in respective parallel planes, for example, to thereby constitute first and second shelves. First bonding pads or contacts (“housing pads”) may be provided on the first surface, which may electrically connect or interconnect with first pads on the integrated circuit (“IC pads”), and second housing pads may be provided on the second surface, which can electrically connect or interconnect with second IC pads. Thus, the IC pads connect to corresponding housing pads on the inner periphery of the housing that are above and below one another.

Abstract: A light-receiving element includes an InP substrate 1, a light-receiving layer 3 having an MQW and located on the InP substrate 1, a contact layer 5 located on the light-receiving layer 3, a p-type region 6 extending from a surface of the contact layer 5 to the light-receiving layer, and a p-side electrode 11 that forms an ohmic contact with the p-type region. The light-receiving element is characterized in that the MQW has a laminated structure including pairs of an InxGa1-xAs (0.38?x?0.68) layer and a GaAs1-ySby (0.25?y?0.73) layer, and in the GaAs1-ySby layer, the Sb content y in a portion on the InP substrate side is larger than the Sb content y in a portion on the opposite side.

Abstract: Solid state radiation transducer (SSRT) assemblies and method for making SSRT assemblies. In one embodiment, a SSRT assembly comprises a first substrate having an epitaxial growth material and a radiation transducer on the first substrate. The radiation transducer can have a first semiconductor material grown on the first substrate, a second semiconductor material, and an active region between the first and second semiconductor materials. The SSRT can also have a first contact electrically coupled to the first semiconductor material and a second contact electrically coupled to the second semiconductor material. The first substrate has an opening through which radiation can pass to and/or from the first semiconductor material.

Abstract: The invention relates to a multispectral imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ? lying within a set of wavelengths to which said structure is sensitive, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets (Eij) of four individual detection pixels, a first individual detection pixel (P?1) comprising a first diffraction grating (R?1) sensitive to a first subset of wavelengths, a second individual detection pixel (P?2) comprising a second diffraction grating (R?2) sensitive to a second subset of wavelengths, a third individual detection pixel (P?3) comprising a third diffraction grating (R?3) sensitive to a third subset of wavelengths and a fourth individual detection pixel (P??) not comprising a wavelength-selective diffraction grating, the first, second and third subsets of wavelengths belonging to the set of wavelengths to which said struc

Abstract: Provided is a biological component detection device with which a biological component can be detected at high sensitivity by using an InP-based photodiode in which a dark current is reduced without using a cooling mechanism and the sensitivity is extended to a wavelength of 1.8 ?m or more. An absorption layer 3 has a multiple quantum well structure composed of group III-V semiconductors, a pn-junction 15 is formed by selectively diffusing an impurity element in the absorption layer, and the concentration of the impurity element in the absorption layer is 5×1016/cm3 or less, the diffusion concentration distribution control layer has an n-type impurity concentration of 2×1015/cm3 or less before the diffusion, the diffusion concentration distribution control layer having a portion adjacent to the absorption layer, the portion having a low impurity concentration.

Abstract: An infrared photodetector including a layer structure of an intermediate layer, and a quantum dot layer having a narrower band gap than the intermediate layer and including a plurality of quantum dots alternately stacked, and detecting photocurrent generated when infrared radiation is applied to the layer structure to thereby detect the infrared radiation, the infrared photodetector further including a first barrier layer provided on one side of the quantum dot layer and having a larger band gap than the intermediate layer; and a second barrier layer provided on the other side of the quantum dot layer and having a larger band gap than the intermediate layer.

Abstract: The invention comprises an optoelectronic platform with a carbon-based conduction layer and a layer of colloidal quantum dots on top as light absorbing material. Photoconductive gain on the order of 106 is possible, while maintaining de operating voltage low. The platform can be used as a transistor.

Abstract: An infrared detector having a hole barrier region adjacent to one side of an absorber region, an electron barrier region adjacent to the other side of the absorber region, and a semiconductor adjacent to the electron barrier.

Abstract: The infrared photodetector includes a contact layer formed over a semiconductor substrate 10, a quantum dot stack 24 formed on the contact layer 12 and including intermediate layers 22 and quantum dots 20 which are alternately stacked, and a contact layer 26 formed on the quantum dot stack 24. One of the plurality of intermediate layers, which is in contact with the contact layer, has an n-type impurity doped region 16 formed on a side nearer the interface with the contact layer 12.

Abstract: An electro-optic device is disclosed. The electro-optic device includes an insulating layer, a first semiconducting region disposed above the insulating layer and being doped with doping atoms of a first conductivity type, a second semiconducting region disposed above the insulating layer and being doped with doping atoms of a second conductivity type and an electro-optic active region disposed above the insulating layer and between the first semiconducting region and the second semiconducting region. The electro-optic active region includes a first partial active region and a second partial active region and an insulating structure in between. The insulating structure extends perpendicular to the surface of the insulating layer such that there is no overlap of the first partial active region and the second partial active region in the direction perpendicular to the surface of the insulating layer. A method for manufacturing is also disclosed.

Abstract: An optoelectronic device is disclosed. The optoelectronic device comprises an active layer and a conducting network layer which comprises a plurality of interconnected metal nanowires and a layer of transparent conducting material in electrical contact with the active layer. The conducting network layer of interconnected metal nanowires is disposed on the layer of transparent conducting material. Above the active layer, light passes through the transparent conducting material to reach the active layer. Each of the nanowires has an elongate, non-spherical configuration and aggregate nanowire length oriented to extend laterally through a plane of the conducting network layer. This provides lengthwise contact of the nanowires to the transparent conducting material.

Abstract: Photodetectors and integrated circuits including photodetectors are disclosed. A photodetector in accordance with the present invention comprises a silicon-on-insulator (SOI) structure resident on a first substrate, the SOI structure comprising a passive waveguide, and a III-V structure bonded to the SOI structure, the III-V structure comprising a quantum well region, a hybrid waveguide, coupled to the quantum well region and the SOI structure adjacent to the passive waveguide, and a mesa, coupled to the quantum well region, wherein when light passes through the hybrid waveguide, the quantum well region detects the light and generates current based on the light detected.

Abstract: Two-terminal multi junction photodetectors and focal plane arrays for multi-color detection or imaging acquisition can be formed by connecting photodiodes with different bandgaps or wavelengths, through tunnel diodes, in series with the same polarization. Under reverse bias in the dark, the total current going through such multi junction photodetectors is dictated by the smallest reverse saturation current of the photodiodes. When in operating mode, a set of light sources with different wavelengths corresponding to each individual photodiode can be used to optically bias all the photodiodes except the detecting photodiode Under illumination, all other photodiodes work in the photovoltaic mode and have much higher maximum possible reverse currents than the detecting photodiode. As a result, the total current of the multi junction photodetector is dictated by the detecting photodiode.

Abstract: In accordance with an example embodiment of the present invention, an apparatus including a nanopillar and a graphene film, the graphene film being in contact with a first end of the nanopillar, wherein the nanopillar includes a metal, the contact being configured to form an intrinsic field region in the graphene film, and wherein the apparatus is configured to generate a photocurrent from a photogenerated charge carrier in the intrinsic field region.

Abstract: A method of fabricating a frontside-illuminated inverted quantum well infrared photodetector may include providing a quantum well wafer having a bulk substrate layer and a quantum material layer, wherein the quantum material layer includes a plurality of alternating quantum well layers and barrier layers epitaxially grown on the bulk substrate layer. The method further includes applying at least one frontside common electrical contact to a frontside of the quantum well wafer, bonding a transparent substrate to the frontside of the quantum well wafer, thinning the bulk substrate layer of the quantum well wafer, and etching the quantum material layer to form quantum well facets that define at least one pyramidal quantum well stack. A backside electrical contact may be applied to the pyramidal quantum well stack. In one embodiment, a plurality of quantum well stacks is bonded to a read-out integrated circuit of a focal plane array.

Abstract: A method of fabricating a frontside-illuminated inverted quantum well infrared photodetector may include providing a quantum well wafer having a bulk substrate layer and a quantum material layer, wherein the quantum material layer includes a plurality of alternating quantum well layers and barrier layers epitaxially grown on the bulk substrate layer. The method further includes applying at least one frontside common electrical contact to a frontside of the quantum well wafer, bonding a transparent substrate to the frontside of the quantum well wafer, thinning the bulk substrate layer of the quantum well wafer, and etching the quantum material layer to form quantum well facets that define at least one pyramidal quantum well stack. A backside electrical contact may be applied to the pyramidal quantum well stack. In one embodiment, a plurality of quantum well stacks is bonded to a read-out integrated circuit of a focal plane array.

Abstract: A method for manufacturing a solar cell including a substrate, a first electrode layer, a semiconductor layer, and a second electrode layer, includes forming a first sacrificial layer on a portion of a surface of the substrate; forming the first electrode layer on the substrate and on the first sacrificial layer; and dividing the first electrode layer by removing the first sacrificial layer and a portion of the first electrode layer formed on the first sacrificial layer.

Abstract: A quantum dot light emitting device includes; a substrate, a first electrode disposed on the substrate, a second electrode disposed substantially opposite to the first electrode, a first charge transport layer disposed between the first electrode and the second electrode, a quantum dot light emitting layer disposed between the first charge transport layer and one of the first electrode and the second electrode, and at least one quantum dot including layer disposed between the quantum dot light emitting layer and the first charge transport layer, wherein the at least one quantum dot including layer has an energy band level different from an energy band level of the quantum dot light emitting layer.

Abstract: A photosensitive device (100), the photosensitive device (100) comprising a substrate (101) and a plurality of vertically aligned nanowire diodes (102 to 105) provided on and/or in the substrate (101).

Abstract: One of an electric wiring substrate and a retaining member includes a section having an absorptance with respect to a laser beam, and the other one of the electric wiring substrate and the retaining member includes a section having a transmittance with respect to the laser beam. The electric wiring substrate and the retaining member are welded to each other by irradiation with a laser beam. At this time, the electric wiring substrate and the retaining member are welded to each other at least at a part of an outer peripheral section of the electric wiring substrate.

Abstract: The present invention provides a light receiving element array etc., having a high light-reception sensitivity in the near-infrared region, an optical sensor device, and a method for producing the light receiving element array. A light receiving element array 55 includes an n-type buffer layer 2 disposed on an InP substrate 1, an absorption layer 3 having a type-II MQW, a contact layer 5 disposed on the absorption layer, and a p-type region extending to the n-type buffer layer 2 through the absorption layer 3, wherein the p-type region formed by selective diffusion is separated from the p-type region of an adjacent light receiving element by a region that is not subjected to selective diffusion, and, in the n-type buffer layer, a p-n junction 15 is formed on a crossed face of a p-type carrier concentration of the p-type region and an n-type carrier concentration of the buffer layer.

Abstract: The invention provides a new class of photoconductive materials and devices, and methods for obtaining high internal photoconductive gain. The devices include a semiconductor or material with an electronic band gap provided in a confined geometry and which exhibits multi-exciton generation (MEG) when illuminated with photons with energies above the threshold for MEG. Due to carrier-carrier Coulombic interactions, multi-excitons within the confined material efficiently recombine via Auger recombination, in which a carrier from one exciton is excited to a higher energy level relative to the band edge. Carriers excited by Auger recombination are subsequently trapped by trap states that capture carriers excited high above the band edge more efficiently than carriers near the band edge. Carriers trapped by the trap states allow for the collection and recirculation of untrapped carriers of opposite charge when used as a photoconductive device, producing high internal photoconductive gain.

Abstract: Optoelectronic device modules, arrays optoelectronic device modules and methods for fabricating optoelectronic device modules are disclosed. The device modules are made using a starting substrate having an insulator layer sandwiched between a bottom electrode made of a flexible bulk conductor and a conductive back plane. An active layer is disposed between the bottom electrode and a transparent conducting layer. One or more electrical contacts between the transparent conducting layer and the back plane are formed through the transparent conducting layer, the active layer, the flexible bulk conductor and the insulating layer. The electrical contacts are electrically isolated from the active layer, the bottom electrode and the insulating layer.

Abstract: An electro-optical device includes a substrate on which first and second electrodes are formed. A plurality of nanoparticles are arrayed on the surface of the substrate between the first and second electrodes. The arrayed nanoparticles exhibit plasmonic activity in at least one wavelength band. A plurality of linking molecules are coupled between respective adjacent ones of the nanoparticles and between each of the electrodes and nanoparticles that are adjacent to the electrodes. The linking molecules are selected to exhibit photo-activity that is complementary to the arrayed nanoparticles.

Abstract: This invention describes a field-effect transistor in which the channel is formed in an array of quantum dots. In one embodiment the quantum dots are cladded with a thin layer serving as an energy barrier. The quantum dot channel (QDC) may consist of one or more layers of cladded dots. These dots are realized on a single or polycrystalline substrate. When QDC FETs are realized on polycrystalline or nanocrystalline thin films they may yield higher mobility than in conventional nano- or microcrystalline thin films. These FETs can be used as thin film transistors (TFTs) in a variety of applications. In another embodiment QDC-FETs are combined with: (a) coupled quantum well SWS channels, (b) quantum dot gate 3-state like FETs, and (c) quantum dot gate nonvolatile memories.

Abstract: Embodiments of the subject invention relate to a method and apparatus for infrared (IR) detection. Organic layers can be utilized to produce a phototransistor for the detection of IR radiation. The wavelength range of the IR detector can be modified by incorporating materials sensitive to photons of different wavelengths. Quantum dots of materials sensitive to photons of different wavelengths than the host organic material of the absorbing layer of the phototransistor can be incorporated into the absorbing layer so as to enhance the absorption of photons having wavelengths associated with the material of the quantum dots. A photoconductor structure can be used instead of a phototransistor. The photoconductor can incorporate PbSe or PbS quantum dots. The photoconductor can incorporate organic materials and part of an OLED structure. A detected IR image can be displayed to a user. Organic materials can be used to create an organic light-emitting device.

Abstract: It is highly desirable to design a monolithic image sensor (and array), which could offer high quantum efficiency over broad spectral ranges, and the possibility to rapidly and randomly address any element in the array. This invention utilizes the growth of semiconductor nanowires such as Si, Ge, Si:Ge, ZnO, or their alloys based nanowires on standard substrates to create multispectral image sensors and photovoltaic cells having these highly desirable features.

Abstract: An image pickup device, a visibility support apparatus, a night vision device, a navigation support apparatus, and a monitoring device are provided in which noise and dark current are suppressed to thereby provide clear images regardless of whether it is day or night. The device includes a light-receiving layer 3 having a multi-quantum well structure and a diffusion concentration distribution control layer 4 disposed on the light-receiving layer so as to be opposite an InP substrate 1, wherein the light-receiving layer has a band gap wavelength of 1.65 to 3 ?m, the diffusion concentration distribution control layer has a lower band gap energy than InP, a pn junction is formed for each light-receiving element by selective diffusion of an impurity element, and the impurity selectively diffused in the light-receiving layer has a concentration of 5×1016/cm3 or less.

Abstract: An electron transporting surfactant is added to a raw material solution such that the electron transporting surfactant is coordinated on the surfaces of quantum dots, and after the dispersion solvent is evaporated by vacuum drying, the immersion in a solvent containing a hole transporting surfactant prepares a quantum dot dispersed solution with a portion of the electron transporting surfactant replaced with the hole transporting surfactant. The quantum dot dispersed solution is applied onto a substrate to prepare a hole transport layer and a quantum dot layer at the same time, and thereby to achieve a thin film which has a two-layer structure.

Abstract: Devices (e.g., optoelectronic devices such as solar cells and infrared or THz photodetectors) with a nanomaterial having vertically correlated quantum dots with built-in charge (VC Q-BIC) and methods of making such devices. The VC Q-BIC material has two or more quantum dot layers, where the layers have quantum dots (individual quantum dots or quantum dot clusters) in a semiconductor material, and adjacent quantum dot layers are separated by a spacer layer of doped semiconductor material. The VC-QBIC nanomaterial provides long photocarrier lifetime, which improves the responsivity and sensitivity of detectors or conversion efficiency in solar cells as compared to previous comparable devices.

Abstract: An optoelectronic device includes a first electrode, a quantum dot layer disposed on the first electrode including a plurality of quantum dots, a fullerene layer disposed directly on the quantum dot layer wherein the quantum dot layer and the fullerene layer form an electronic heterojunction, and a second electrode disposed on the fullerene layer. The device may include an electron blocking layer. The quantum dot layer may be modified by a chemical treatment to exhibit in creased charge carrier mobility.

Abstract: There is provided a photoconductive element capable of increasing an output and detection sensitivity by increasing resistivity as the entire element. The photoconductive element is a photoconductive element capable of generating or detecting an electromagnetic wave when light is emitted thereto. The photoconductive element includes a photoconductive layer having a semiconductor layer whose resistivity changes when light is emitted to thereby generate or detect an electromagnetic wave; and a plurality of electrodes provided in contact with the semiconductor layer. The resistivity of the semiconductor layer changes in a thickness direction of intersecting a surface of the semiconductor layer contacting the electrodes. Assuming that the semiconductor layer includes a first region and a second region which is farther away from the electrodes in the thickness direction than the first region, the resistivity in the first region is greater than the resistivity in the second region.

Abstract: The lattice mismatching between a Ge layer and a Si layer is as large as about 4%. Thus, when the Ge layer is grown on the Si layer, penetration dislocation is introduced to cause leakage current at the p-i-n junction. Thereby, the photo-detection sensitivity is reduced, and the reliability of the element is also lowered. Further, in the connection with a Si waveguide, there are also problems of the reflection loss due to the difference in refractive index between Si and Ge, and of the absorption loss caused by a metal electrode.

Abstract: A photodetector 1 according to an embodiment of the present invention includes: an n-type InAs substrate 12; an n-type InAs buffer layer 14 formed on the n-type InAs substrate 12; an n-type InAs light absorbing layer 16 formed on the n-type InAs buffer layer 14; an InAsXPYSb1-X-Y cap layer 18 (X?0, Y>0) formed on the n-type InAs light absorbing layer 16; a first inorganic insulating film 20 formed on the cap layer 18, and having an opening portion 20h in a deposition direction; a p-type impurity semiconductor region 24 fowled by diffusing a p-type impurity from the opening portion 20h of the first inorganic insulating film 20, and reaching from the cap layer 18 to an upper layer of the n-type InAs light absorbing layer 16; and a second inorganic insulating film 22 formed on the first inorganic insulating film 20 and on the p-type impurity semiconductor region 24.

Abstract: This disclosure provides polymer electrolytes for dye-sensitized solar cells that can not only prevent electrolytes from leaking, but also exhibit a higher solar conversion efficiency when compared with conventional polymer electrolytes, whereby the polymer electrolytes are applicable to a process for manufacturing dye-sensitized solar cells with a large surface area or flexible dye-sensitized solar cells, and methods for manufacturing modules of dye-sensitized solar cells using the same.

Abstract: A photodetector includes one or more photodiodes and a signal processing circuit. Each photodiode includes a transparent first electrode, a second electrode, and a heterojunction interposed between the first electrode and the second electrode. Each heterojunction includes a quantum dot layer and a fullerene layer disposed directly on the quantum dot layer. The signal processing circuit is in signal communication each the second electrode. The photodetector may be responsive to wavelengths in the infrared, visible, and/or ultraviolet ranges. The quantum dot layer may be treated with a chemistry that increases the charge carrier mobility of the quantum dot layer.

Abstract: A light-receiving element includes a group III-V compound semiconductor stacked structure that includes an absorption layer having a pn-junction therein. The stacked structure is formed on a group III-V compound semiconductor substrate. The absorption layer has a multi- quantum well structure composed of group III-V compound semiconductors, and the pn-junction is formed by selectively diffusing an impurity element into the absorption layer. A diffusion concentration distribution control layer composed of a III-V group semiconductor is disposed in contact with the absorption layer on a side of the absorption layer opposite the side adjacent to the group III-V compound semiconductor substrate. The bandgap energy of the diffusion concentration distribution control layer is smaller than that of the group III-V compound semiconductor substrate. The concentration of the impurity element selectively diffused in the diffusion concentration distribution control layer is 5×1016/cm3 or less toward the absorption layer.

Abstract: A method for manufacturing an electronic-photonic device. Epitaxially depositing an n-doped III-V composite semiconductor alloy buffer layer on a crystalline surface of a substrate at a first temperature. Forming an active layer on the n-doped III-V epitaxial composite semiconductor alloy buffer layer at a second temperature, the active layer including a plurality of spheroid-shaped quantum dots. Depositing a p-doped III-V composite semiconductor alloy capping layer on the active layer at a third temperature. The second temperature is less than the first temperature and the third temperature. The active layer has a photoluminescence intensity emission peak in the telecommunication C-band.

Abstract: Embodiments of the invention are directed to an IR photodetector that broadly absorbs electromagnetic radiation including at least a portion of the near infrared (NIR) spectrum. The IR photodetector comprises polydispersed QDs of PbS and/or PbSe. The IR photodetector can be included as a layer in an up-conversion device when coupled to a light emitting diode (LED) according to an embodiment of the invention.

Abstract: Provided are a semiconductor device and an optical sensor device, each having reduced dark current, and detectivity extended toward longer wavelengths in the near-infrared. Further, a method for manufacturing the semiconductor device is provided. The semiconductor device 50 includes an absorption layer 3 of a type II (GaAsSb/InGaAs) MQW structure located on an InP substrate 1, and an InP contact layer 5 located on the MQW structure. In the MQW structure, a composition x (%) of GaAsSb is not smaller than 44%, a thickness z (nm) thereof is not smaller than 3 nm, and z??0.4x+24.6 is satisfied.

Abstract: A photoelectric conversion element of the present invention comprises: a first semiconductor layer of a first conductivity type; a first electrode arranged on the back side of the first semiconductor layer a second semiconductor layer of a second conductivity type, the second semiconductor layer on the light-receiving side of the first semiconductor layer; a light-receiving face-side electrode provided on the light-receiving side of the second semiconductor layer; a second electrode arranged on the back side of the first semiconductor layer, and electrically separated from the first semiconductor layer, but connected to the second semiconductor layer; and a penetrating-connecting section penetrating the first semiconductor layer, and connecting the light-receiving face-side electrode with the second electrode, wherein the photoelectric conversion element is characterized in that the first electrode and the second electrode are arranged equidistantly apart from a central axis passing through a center of the ph

Abstract: Methods and devices for solar cell interconnection are provided. In one embodiment, the method includes physically alloying the ink metal to the underlying foil (hence excellent adhesion and conductivity with no pre-treatment), and by fusing the solid particles in the ink on the surface (eliminating any organic components) so that the surface is ideally suited for good conductivity and adhesion to an overlayer of finger ink, which is expected to be another adhesive. In some embodiments, contact resistance of conductive adhesives are known to be much lower on gold or silver than on any other metals.

Abstract: A composite material is described. The composite material comprises semiconductor nanocrystals, and organic molecules that passivate the surfaces of the semiconductor nanocrystals. One or more properties of the organic molecules facilitate the transfer of charge between the semiconductor nanocrystals. A semiconductor material is described that comprises p-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of electrons in the semiconductor material being greater than or equal to a mobility of holes. A semiconductor material is described that comprises n-type semiconductor material including semiconductor nanocrystals. At least one property of the semiconductor material results in a mobility of holes in the semiconductor material being greater than or equal to a mobility of electrons.

Abstract: The present invention relates to a composition for photon energy up-conversion, a system comprising said composition and to uses of said composition and said system.

Abstract: An optoelectronic device including two spaced apart electrodes; and at least one layer containing ternary core/shell nanocrystals disposed between the spaced electrodes and having ternary semiconductor cores containing a gradient in alloy composition and wherein the ternary core/shell nanocrystals exhibit single molecule non-blinking behavior characterized by on times greater than one minute or radiative lifetimes less than 10 ns.

Abstract: Silicon, silicon-germanium alloy, and germanium nanowire optoelectronic devices and methods for fabricating the same are provided. According to one embodiment, a P-I-N device is provided that includes a parallel array of intrinsic silicon, silicon-germanium or germanium nanowires located between a p+ contact and an n+ contact. In certain embodiments, the intrinsic silicon and germanium nanowires can be fabricated with diameters of less than 4.9 nm and 19 nm, respectively. In a further embodiment, vertically stacked silicon, silicon-germanium and germanium nanowires can be formed.

Abstract: An active layer having a p-type quantum dot structure is disposed over a lower cladding layer made of semiconductor material of a first conductivity type. An upper cladding layer is disposed over the active layer. The upper cladding layer is made of semiconductor material, and includes a ridge portion and a cover portion. The ridge portion extends in one direction, and the cover portion covers the surface on both sides of the ridge portion. A capacitance reducing region is disposed on both sides of the ridge portion and reaching at least the lower surface of the cover portion. The capacitance reducing region has the first conductivity type or a higher resistivity than that of the ridge portion, and the ridge portion has a second conductivity type. If the lower cladding layer is an n-type, the capacitance reducing region reaches at least the upper surface of the lower cladding layer.

Abstract: A diffraction grating coupled infrared photodetector for providing high performance detection of infrared radiation is described. The photodetector includes a three-dimensional diffractive resonant optical cavity formed by a diffraction grating that resonates over a range of infrared radiation wavelengths. By placing a limited number of p/n junctions throughout the photodetector, the photodetector thermal noise is reduced due to the reduction in junction area. By retaining signal response and reducing the noise, the sensitivity increases at a given operating temperature when compared to traditional photovoltaic and photoconductive infrared photodetectors up to the background limit. The photodetector device design can be used with a number of semiconductor material systems, can form one- and two-dimensional focal plane arrays, and can readily be tuned for operation in the long wavelength infrared and the very long wavelength infrared where sensitivity and noise improvements are most significant.