A beta-voltaic device made up of silica covered scintillating particles incorporated within an isotope absorbing layer to produce an improved power source. Lost beta particles are converted to UV light which is also converted to power in a beta-voltaic converter. The addition of the scintillating particles effectively increases the power efficiency of a BV device while maintaining the slim profile and smaller size of the power source. This arrangement makes possible implementation in space, defense, intelligence, medical implants, marine biology and other applications.

A multijunction solar cell assembly and its method of manufacture including first and second discrete semiconductor body subassemblies, each semiconductor body subassembly including first, second and third lattice matched subcells; a graded interlayer adjacent to the third solar subcell and functioning as a lateral conduction layer; and a fourth solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the third solar subcell; wherein the average band gap of all four cells is greater than 1.44 eV.

A multijunction solar cell assembly and its method of manufacture including first and second discrete semiconductor body subassemblies, each semiconductor body subassembly including first, second and third lattice matched subcells; a graded interlayer adjacent to the third solar subcell and functioning as a lateral conduction layer; and a fourth solar subcell adjacent to said graded interlayer being lattice mismatched with respect to the third solar subcell; wherein the average band gap of all four cells is greater than 1.44 eV.

A photovoltaic charging system having a narrow-spectrum light source attuned to an absorption band of a photovoltaic cell may achieve power delivery of at least 0.5 mW/10,000 μm.sup.2 upon stimulation of the photovoltaic cell with narrow-spectrum light.

A photovoltaic charging system having a narrow-spectrum light source attuned to an absorption band of a photovoltaic cell may achieve power delivery of at least 0.5 mW/10,000 μm.sup.2 upon stimulation of the photovoltaic cell with narrow-spectrum light.

The use of photovoltaic (PV) cells to convert solar energy to electricity is becoming increasingly prevalent; however, there are still significant limitations associated with the widespread adoption of PV cells for electricity needs. There is a clear need for a high efficiency solar power system that supplies electricity at a competitive cost and that provides for an on-demand supply of electricity as well as energy storage. By combining aspects of concentrated solar power and concentrated photovoltaics, the present invention provides a device that enables the conversion of sunlight to electricity at very high efficiencies and that enables the transmission of thermal energy to heat storage devices for later use. The disclosed device enables transmissive CPV through the use of a multijunction PV cell mounted on a transparent base. The use of a multijunction cell allows for highly efficient absorption of light above the bandgap of the lowest bandgap subcell. The transparent base permits transmission of a high percentage of the remaining light below the bandgap of the lowest bandgap subcell. The present invention also discloses a method of generating electricity through the use of a transmissive CPV device. Sunlight is concentrated onto one or more surfaces of the device. High energy light is absorbed by a multijunction PV cell and converted directly to electricity, while low energy light is transmitted through the device into a thermal storage device, which may then be coupled to a heat engine to generate dispatchable electricity.

The use of photovoltaic (PV) cells to convert solar energy to electricity is becoming increasingly prevalent; however, there are still significant limitations associated with the widespread adoption of PV cells for electricity needs. There is a clear need for a high efficiency solar power system that supplies electricity at a competitive cost and that provides for an on-demand supply of electricity as well as energy storage. By combining aspects of concentrated solar power and concentrated photovoltaics, the present invention provides a device that enables the conversion of sunlight to electricity at very high efficiencies and that enables the transmission of thermal energy to heat storage devices for later use. The disclosed device enables transmissive CPV through the use of a multijunction PV cell mounted on a transparent base. The use of a multijunction cell allows for highly efficient absorption of light above the bandgap of the lowest bandgap subcell. The transparent base permits transmission of a high percentage of the remaining light below the bandgap of the lowest bandgap subcell. The present invention also discloses a method of generating electricity through the use of a transmissive CPV device. Sunlight is concentrated onto one or more surfaces of the device. High energy light is absorbed by a multijunction PV cell and converted directly to electricity, while low energy light is transmitted through the device into a thermal storage device, which may then be coupled to a heat engine to generate dispatchable electricity.

A monocrystalline germanium wafer that increases the open-circuit voltage of multijunction solar cells, a method for preparing the monocrystalline germanium wafer and a method for preparing an ingot from which the monocrystalline germanium wafer is prepared. The monocrystalline germanium wafer that increases the open-circuit voltage of the bottom cell of multijunction solar cells is prepared by adjusting the amounts of the co-dopants silicon and gallium in the monocrystalline germanium wafer, the ratio of silicon to gallium in the preparation of the monocrystalline germanium.

A transceiver assembly for a wireless power transfer system includes a transceiver system comprising a photodiode assembly, a voltage converter and a light emitting diode and a photodiode. The photodiode assembly may be configured to receive a high-power laser beam from a transmitter and to convert the high-power laser beam to electrical energy. The voltage converter may be configured to adjust an input impedance based on a voltage measure of the photodiode assembly so as to maximize power transfer from the photodiode assembly to an energy storage device electrically coupled to the voltage converter. The light emitting diode and the photodiode may be configured to enable free space optical communication with the transmitter. The light emitting diode may emit signals indicating a presence and a location of the transceiver to the transmitter at least when the energy storage device requires a charge.

A semiconductor structure including a bonding layer connecting a first semiconductor wafer layer to a second semiconductor wafer layer, the bonding layer including an electrically conductive carbonaceous component and a binder component.