Sumitomo Electric Industries, Limited

Mitsubishi Materials Corporation

Saburo Tanaka

Hideo Itozaki

Shuji Yazu

Tetsuji Jodai

Nobuhiko Fujita

Takashi Matsuura

Hidenori Nakanishi

Kenjiro Higaki

Naoji Fujimori

Tadakazu Kobayashi

Tatsuoki Nagaishi

Keizo Harada

Akira Yoshioka

Takeshi Yamaguchi

Akiyoshi Tatsui

Hideomi Saito

Takahiro Imai

Noriyuki Yoshida

Satoshi Takano

Noriki Hayashi

Kenji Miyazaki

Hisao Hattori

Hajime Hitotsuyanagi

Syoji Nakagama

Kazuhiko Fukushima

Hiroyuki Morozumi

A tunnel junction type Josephson device includes a pair of superconductor layers formed of a compound oxide superconductor material and an insulator layer formed between the pair of superconductor layers. The insulator layer is formed of a compound oxide which is composed of the same constituent elements as those of the compound oxide superconductor material of the superconductor layers but with an atomic ratio which does not present a superconductivity characteristics. In addition, the superconductor layers and the insulator layer are continuously formed while supplying oxygen.

Tunnel junction type josephson device

A high-temperature superconducting thin film of compound oxide selected from the group consisting of:

Superconducting thin film and a method for preparing the same

There is disclosed a device for forming a thin film on a substrate by irradiating a target of a compound oxide superconducting material with a laser beam and evaporating on the substrate a thin film corresponding to a composition of the target in an oxygen ambient atmosphere by laser evaporation, a scanning optical system for causing the laser beam to scan being disposed in an optical path of the laser beam.

Device for forming a compound oxide superconducting thin film

A Josephson junction device includes a substrate, an oxide thin film formed on a portion of the principal surface of the substrate, which is constituted of a single crystal of which lattices shift at angle of 45.degree. to that of the principal surface of the substrate. One of the two portions of the oxide superconductor thin film is formed on the oxide thin film and the other portion of the superconductor thin film is formed on the principal surface of the substrate directly so that the lattices of the two portions of the oxide superconductor thin film are respectively linear up to those of the oxide thin film and the principal surface of the substrate and the grain boundary. The grain boundary which constitutes a weak link of the Josephson junction is formed just on the step portion formed of the oxide thin film.

Josephson junction device of oxide superconductor and process for

A Josephson junction device is disclosed that includes a single crystalline substrate having a NaCl type crystal structure. The device includes a principal surface having two horizontal planes and a slope inclined at an angle of 5.degree. to 30.degree. between the two horizontal planes. An oxide superconductor thin film is formed on the principal surface of the substrate, which includes first and a second superconducting portions of a first single crystalline oxide superconductor and a second single crystalline oxide superconductor respectively positioned on the two horizontal planes of the substrate. A junction portion of a single crystalline oxide superconductor has a different crystal orientation from the first and the second superconducting portions, and is positioned on the slope of the substrate. Two grain boundaries between each of the first and the second superconducting portions and the junction portion constitute one weak link of the Josephson junction.

Josephson junction device formed of oxide superconductor

A SQUID includes a substrate and a superconducting current path of a patterned oxide superconductor material thin film formed on a surface of the substrate. A c-axis of an oxide crystal of the oxide superconductor material thin film is oriented in parallel to the surface of the substrate.

Superconducting quantum interference device formed of oxide

For manufacturing a superconducting device having a tunnel junction formed of an extremely thin insulator layer sandwiched between a pair of oxide superconductor thin films, a first superconducting layer of oxide superconductor thin film is formed on a substrate, and a MgO thin film is deposited on the first superconducting layer at a substrate temperature of not higher than 200.degree. C. The MgO thin film is heat-treated so that crystallinity of the deposited MgO thin film is improved, and thereafter, a second superconducting layer of oxide superconductor thin film is formed on the MgO thin film.

Method for manufacturing tunnel junction type josephson device composed

A Josephson junction device comprising a single crystalline substrate including a principal surface, a layer of the same material as the substrate formed on the principal surface of the substrate so as to form a step on the principal surface, and an oxide superconductor thin film formed on the principal surface of the substrate. The oxide superconductor thin film includes a first and a second superconducting portions respectively positioned above and below the step, which are constituted of single crystals of the oxide superconductor, a junction portion between the first and the second superconducting portions, which is constituted of a single crystal of the oxide superconductor of which crystal orientation is different from those of the first and second superconducting portions, and grain boundaries between the first superconducting portion and the junction portion and between the second superconducting portion and the junction portion, which constitute one weak link of the Josephson junction.

Josephson junction device formed of oxide superconductor and process for

There is disclosed a superconductor junction structure comprising: a first superconducting layer of an oxide superconductor formed in a desired pattern on a substrate; a non-superconducting layer of a non-superconductor formed on at least a part of the side faces of the first superconducting layer, a portion of the surface of the substrate near the part, and a top face of the first superconducting layer; and a second superconducting layer of the oxide superconductor formed on the non-superconducting layer, the non-superconducting layer being formed thin at the part, and forming a tunnel barrier. And further there is disclosed a process for fabricating a superconductor junction structure comprising: the first step of forming a first superconducting layer of an oxide superconductor in a desired pattern on a substrate; the second step of forming a non-superconducting layer of a non-superconductor formed on at least a part of the side faces of the first superconducting layer, a portion of the surface of the substrate near the part, and a top face of the first superconducting layer by depositing the non-superconductor from the above; and the third step of forming a second superconducting layer of the oxide superconductor on the non-superconducting layer.

Superconductor junction structure including two oxide superconductor

Device for forming a compound oxide superconductor thin film

An outer surface of a superconducting thin film of compound oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-.delta. deposited on a substrate such as MgO and SrTiO.sub.3 is protected with a protective layer which is composed of amorphous inorganic material such as inorganic glass, amorphous oxide.

A Josephson junction device comprising a single crystalline substrate including a principal surface having two horizontal planes and a smooth slope between the two horizontal planes, and an oxide superconductor thin film formed on the principal surface of the substrate. The oxide superconductor thin film includes a first and a second superconducting portions of a single crystalline oxide superconductor respectively positioned on the two horizontal planes of the substrate, a junction portion of a single crystalline oxide superconductor having a different crystal orientation from the two superconducting portions positioned on the slope of the substrate and two grain boundaries between each of the two superconducting portions and the junction portion. The grain boundaries constitutes one weak link of the Josephson junction.

Step-edged grain boundary Josephson junction with 5 to 30 degrees

A method for forming an oxide superconductor thin film having different thickness portions, in a process for manufacturing a superconductor device, includes the step of forming an oxide superconductor thin film having a uniform thickness on a substrates. A portion of the oxide superconductor thin film is etch-removed so that the oxide superconductor thin film has a thin thickness portion. Preferably, before the etching, the oxide superconductor thin film is coated with a metal layer, and the oxide superconductor thin film and the metal layer are etched together by means of a physical dry etching process.

Method for forming continuous oxide superconducting layer having

A Josephson junction device comprising a single crystalline substrate including principal surface, a layer of the same material as the substrate formed on the principal surface of the substrate so as to form a step on the principal surface, and an oxide superconductor thin film formed on the principal surface of the substrate. The oxide superconductor thin film includes a first and a second superconducting portions respectively positioned above and below the step, which are constituted of single crystals of the oxide superconductor, a junction portion between the first and the second superconducting portions, which is constituted of a single crystal of the oxide superconductor of which crystal orientation is different from those of the first and second superconducting portions, and grain boundaries between the first superconducting portion and the junction portion and between the second superconducting portion and the junction portion, which constitute one weak link of the Josephson junction.

Growing community of inventors

Hyogo, Japan

Saburo Tanaka