Conductus, Inc.

Other

University of California

Global Technologies, Inc.

Nathan Newman

Kookrin Char

Yale Deon Harker

Michael Rubin

Stephen M Garrison

Tristan Dieter Juergens

Gregory G Zaharchuk

Kwan Sze Kwok

Francis Yu-Hei Tsang

Scott Arden Ploger

Andre Anders

Randy Wayne Simon

Aharon Kapitulnik

James W Chan

Simone Anders

Theodore Van Duzer

Lei Yu

John M Rowell

Brady F Cole

Anupama Bhat Kaul

Xiaoxan Meng

Jennifer Ross

Tracy Fu

Michael Dickinson

The invention describes a product and a method for generating electrical power directly from nuclear power. More particularly, the invention describes the use of a liquid semiconductor as a means for efficiently converting nuclear energy, either nuclear fission and/or radiation energy, directly into electrical energy. Direct conversion of nuclear energy to electrical energy is achieved by placing nuclear material in close proximity to a liquid semiconductor. Nuclear energy emitted from the nuclear material, in the form of fission fragments or radiation, enters the liquid semiconductor and creates electron-hole pairs. By using an appropriate electrical circuit an electrical load is applied and electrical energy generated as a result of the creation of the electron-hole pairs.

Nuclear voltaic cell

A Josephson junction has inherent resistance which effectively shunts the junction and thereby obviates a separate shunt resistor and thus reduces surface area in an integrated circuit including a plurality of Josephson junctions. The Josephson junction comprises a stacked array of layers of Nb and a superconductor with T >9&deg; K having a penetration depth greater than that of Nb, for example Nb Ti N, with a layer of a conducting material having a resistivity between 200 &mgr;&OHgr;-cm, 1 &OHgr;-cm, such as Ta N in the stack. The Josephson junction can be formed on a supporting substrate such as silicon with a ground plane such as Nb on the substrate and an insulating layer such as SiO separating the ground plane from the stacked array.

Internally shunted Josephson junction device

A constricted glow discharge chamber and method are disclosed. The polarity and geometry of the constricted glow discharge plasma source is set so that the contamination and energy of the ions discharged from the source are minimized. The several sources can be mounted in parallel and in series to provide a sustained ultra low source of ions in a plasma with contamination below practical detection limits. The source is suitable for applying films of nitrides such as gallium nitride and oxides such as tungsten oxide and for enriching other substances in material surfaces such as oxygen and water vapor, which are difficult process as plasma in any known devices and methods. The source can also be used to assist the deposition of films such as metal films by providing low-energy ions such as argon ions.

Constricted glow discharge plasma source

Several methods have been found to make p-type gallium nitride. P-type gallium nitride has long been sought for electronic devices. N-type gallium nitride is readily available. Discovery of p-type gallium nitride and the methods for making it will enable its use in ultraviolet and blue light-emitting diodes and lasers. pGaN will further enable blue photocathode elements to be made. Molecular beam epitaxy on substrates held at the proper temperatures, assisted by a nitrogen beam of the proper energy produced several types of p-type GaN with hole concentrations of about 5.times.10.sup.11 /cm.sup.3 and hole mobilities of about 500 cm.sup.2 /V-sec, measured at 250.degree. K. P-type GaN can be formed of unintentionally-doped material or can be doped with magnesium by diffusion, ion implantation, or co-evaporation. When applicable, the nitrogen can be substituted with other group III elements such as Al.

P-type gallium nitride

A novel method of producing weak-link grain boundary Josephson junctions in high temperature superconducting thin films is disclosed. These junctions are reliably and reproducibly formed on uniform planar substrates (10) by the action of a seed layer (40) placed intermediate the substrate (10) and the superconductor film (20). The superconductor film (22) grown atop the seed (42) is misoriented from the rest of the film (24) by an angle between 5.degree. and 90.degree.. The grain boundary (30) so formed acts as a high quality weak-link junction for superconductor devices. The performance of these junctions can be improved by the addition of buffer layers (50, 60) between the substrate (10) and the superconductor film (20).

Method of forming grain boundary junctions in high temperature

A superconducting electronic circuit device, useful when impedance matching is desired, especially suited to microwave frequencies, consisting of a thin dielectric layer with superconducting layers on both sides. A superconductor such as Yttrium Barium Copper Oxide (YBCO) is formed on a first substrate such as lanthanum aluminate. A protective layer like gold is deposited on the YBCO and a second carrier substrate is bonded to the protected YBCO. The first substrate is then thinned into a thin dielectric film and a second layer of superconductor is epitaxially grown thereon to create the desired circuits.

Method of preparing high temperature superconductor films on opposite

To deposit a plurality of substances on a substrate while the substrate remains in a low pressure oxygen environment, several target carriers are mounted around the edge of a disc and the disc is rotated to position the targets at the focal point of a fixed laser. The target carriers are themselves rotatable in bearings on the disc and are turned by a sun gear that is carried about the same shaft that turns the disc so that the heat of the laser beam is not concentrated at one spot on the surface of the target. All the apparatus is contained in a oxygen chamber. The substrate is heated and the targets are cooled continuously.

Superconductor deposition system

Grain boundary, weak-link junctions are formed at a predermined location of a uniform, planar substrate by depositing superconducting film on two sections of the substrate. The film is grown as a bicrystal having two distinct areas of superconducting film whose crystal lattices are rotated with respect to each other, either in-plane or out-of-plane, by more than 5.degree. and less than 90.degree.. The grain boundary acts as a weak link junction. The film can be induced to grow as a bicrystal by depositing intermediate strata such as seed layers or buffer layers or by modifying the growth conditions during deposition.

Grain boundary junctions in high temperature superconductor films

A HTSC layered structure comprising a substrate such as sapphire, a strontium titanate buffer layer and a HTSC film such as YBa.sub.2 Cu.sub.3 O.sub.7 provides a superconductor having lower surface resistance and a narrower transition temperature.

High temperature superconductor-strontium titanate sapphire structures

A substrate heater for the production of superconducting films utilizing a nickel alloy block uniformly heated with a resistance heating element fully immersed in a brazing material that fills a recess in the block. Massive electric power connectors surround the heating element leads outside the braze material so as to provide a protective heat sink therefor and also to mechanically strengthen the block against warpage.

Growing community of inventors

Montara, CA, United States of America

Nathan Newman