Sumitomo Electric Industries, Limited

Nec Corporation

Research Development Corporation of Japan

International Superconductivity Technology Center

Koji Muranaka

Kenichi Sato

Shoji Tanaka

Katsumi Suzuki

Takeshi Hikata

Youichi Enomoto

Tadataka Morishita

Sadahiko Miura

Takayuki Inoue

Hideaki Zama

In a high frequency transmission line having a dielectric substrate and a conductor line which is provided on the dielectric substrate for allowing electric current to flow therethrough, the conductor line has a non-grain-boundary oxide superconductor layer with twin walls but without grain boundaries. The high frequency transmission line is in the form of a plane circuit. It is preferable that an oriented oxide superconductor layer is provided between the dielectric substrate and the non-grain-boundary oxide superconductor layer.

High frequency transmission line capable of improving an intermodulation

A method of producing a tape-shaped superconducting wire is provided. The wire maintains a high critical temperature and a high critical current density along the overall length thereof. In this method, raw material powder for the oxide superconductor is first charged in a silver sheath and the sheath charged with the powder is subjected to plastic working to prepare a first flat type wire. On the other hand, a second wire consisting of a tape wire formed by coating a surface of a flat type wire having at least an outer surface consisting essentially of silver or a silver alloy with a metal oxide or ceramics, or a tape wire containing ceramics fibers and a binder dissipated by heat treatment is prepared. The first and second wires are layered with each other, and tightly wound in a pancake coil shape. The wires wound in the pancake coil shape are heat treated for sintering the oxide superconductor. After the heat treatment, the first wire is separated from the second wire.

Method for preparing high-temperature superconducting wire

Growing community of inventors

Tokyo, Japan

Koji Muranaka