Abstract: Disclosed is a Radio Frequency (“RF”) Energy Harvesting System (“RFHS”). The RFHS includes a phased array antenna, a power harvesting unit, and a controller. The phased array antenna is configured to receive ambient RF energy and, in response, produce an input power signal. The power harvesting unit is in signal communication with the phased array antenna and includes a rectifier module, storage module, and power threshold module. The power harvesting unit is configured to receive the input power signal and, in response, produce a rectified power signal. The controller is in signal communication with the phased array antenna and may steer the antenna beam of the phased array antenna.

Abstract: Disclosed is a Radio Frequency (“RF”) Energy Harvesting System (“RFHS”). The RFHS includes a phased array antenna, a power harvesting unit, and a controller. The phased array antenna is configured to receive ambient RF energy and, in response, produce an input power signal. The power harvesting unit is in signal communication with the phased array antenna and includes a rectifier module, storage module, and power threshold module. The power harvesting unit is configured to receive the input power signal and, in response, produce a rectified power signal. The controller is in signal communication with the phased array antenna and may steer the antenna beam of the phased array antenna.

Abstract: An anti-reflection nanostructure assembly including an array of nanostructures, wherein each nanostructure of the array includes a proximal end and a distal end, and is tapered from the proximal end to the distal end, and wherein the proximal end of each nanostructure of the array is contiguous with the proximal ends of adjacent nanostructures of the array to form a contiguous layer.

Abstract: An anti-reflection nanostructure assembly including an array of nanostructures, wherein each nanostructure of the array includes a proximal end and a distal end, and is tapered from the proximal end to the distal end, and wherein the proximal end of each nanostructure of the array is contiguous with the proximal ends of adjacent nanostructures of the array to form a contiguous layer.

Abstract: A solar concentrator including a housing having a receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall, an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.

Abstract: A solar concentrator including a housing having a receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall, an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.

Abstract: An apparatus and method for building an optically pumped laser integrated with an electrically driven pump laser is disclosed. The apparatus disclosed comprises an optically pumped laser containing an active layer and an optical pump laser containing an optical mode at least partially overlapping and propagating substantially parallel to optically pumped laser's active layer. The method discloses forming an optically pumped gain element containing an active layer, forming a pump laser containing an optical mode at least partially overlapping and propagating substantially parallel to optically pumped gain element's active layer.

Abstract: The present invention comprises a method and apparatus to increase the efficiency of photovoltaic conversion of light into electrical power and to achieve operation at higher optical power and therefore higher electrical power. Preferred embodiments increase the efficiency of photovoltaic power conversion of any source of a beam of photons by spatially dividing the beams into a plurality of individual beamlets, each beamlet focusing on an active photovoltaic region. The preferred architecture of the apparatus of the invention comprises spatially separated photovoltaic cells to substantially match the pattern of the spatially separated plurality of beamlets. Preferred embodiments result in a significant reduction in ohmic losses and current shunting, thereby increasing photovoltaic conversion efficiencies.

Abstract: An apparatus and methods for an optically pumped laser that has a cascade of light-emitting interband transitions are disclosed. The apparatus disclosed contains multistep interband cascade regions able to generate a plurality of photons for a pump photon absorbed from an optical pump source. The methods disclosed teach how to produce a plurality of photons for a pump photon absorbed from an optical pump source.

Abstract: A waveguide is fabricated by first preparing two waveguide precursor pieces. Each waveguide precursor piece includes a single-crystal substrate, and an epitaxial coating layer of an oxide coating material on the substrate. The oxide substrate material preferably comprises yttrium as a substrate-material cation, and the oxide coating material preferably comprises a coating-material cation selected from the group consisting of ytterbium, thulium, erbium, and holmium. The two substrates are placed together with the coating layers in contact to form a precursor structure. The precursor structure is heated to an elevated diffusion temperature so that the coating layers bond together and the coating materials and the respective substrate materials interdiffuse to form the waveguide having an interdiffused region. A laser beam may be directed through the interdiffused region, while the interdiffused region is optionally optically pumped through one or both of the substrates.

Abstract: The present invention provides a solar cell comprising a substrate, a first buffer layer disposed above the base layer, a second buffer layer disposed above the first buffer layer, a first boron compound layer disposed above the second buffer layer, a second boron compound layer disposed above the first compound layer, and a window layer disposed above the second compound layer, wherein the first compound layer comprises a first type of doping, wherein the second compound layer comprises a second type of doping, wherein the second buffer layer comprises a higher energy bandgap than the first compound layer, and wherein the first buffer layer and the second buffer layer permit a boron content in the first compound layer and the second compound layer to be greater than 3 %.

Abstract: The present invention provides a solar cell comprising a substrate, a first buffer layer disposed above the base layer, a second buffer layer disposed above the first buffer layer, a first boron compound layer disposed above the second buffer layer, a second boron compound layer disposed above the first compound layer, and a window layer disposed above the second compound layer, wherein the first compound layer comprises a first type of doping, wherein the second compound layer comprises a second type of doping, wherein the second buffer layer comprises a higher energy bandgap than the first compound layer, and wherein the first buffer layer and the second buffer layer permit a boron content in the first compound layer and the second compound layer to be greater than 3%.

Abstract: The present invention provides a broadband transmitting protective coating (10) including an AlGaP protective layer (14) deposited on an optical substrate (12) and an anti-reflection film (16) deposited on the AlGaP protective layer (14). The coating (10) is suitable for use with typical infrared and broadband optical substrate materials such as germanium or multi-spectral ZnS. In the case of a germanium substrate (12), the anti-reflection film (16), (16a) preferably consists of a single layer of hard carbon or alternating layers of hard carbon and silicon. In the case of a multi-spectral ZnS substrate (12a), the anti-reflection film (16b) preferably consists of layered Al.sub.2 O.sub.3 /TaO.sub.5 /LaF.sub.3 /MgF.sub.2. The protective coating (10) is preferably deposited on the optical substrate (12) by a metal organic chemical vapor deposition process wherein an initial layer of AlP is nucleated on the substrate (12) at a temperature of approximately 400.degree. C.

Abstract: A doping profile is disclosed for realizing a varactor diode that exhibits a high breakdown voltage V.sub.BR, e.g.,>100 volts, and a capacitance which has a bi-level characteristic. In particular, the capacitance has a C.sub.max level and a C.sub.min level. The doping profile includes two lightly doped regions and, between them, a third region with higher doping. The doping concentrations and widths of the first two regions substantially set the tuning ratio of C.sub.max /C.sub.min, and the doping concentration and width of the third region substantially sets the transition voltage V.sub.TR between the bi-level capacitances.