United States of America As Represented by the Secretary of the Air Force

Other

University of Dayton

Paul N Barnes

Timothy J Haugan

Chakrapani Varanasi

Judy Zhihong Wu

Milan Polak

Rose Emergo

George A Levin

Joseph W Kell

P Terry Murray

The present invention provides a method of making a high temperature superconductor having a doped, nanoparticulate pinning structure. The method includes providing a nanoparticulate pinning material, providing a cuprate material, doping the nanoparticulate pinning material with a dopant to form a doped nanoparticulate material, depositing a layer of the cuprate material on a substrate, and depositing a layer of the doped nanoparticulate material on the layer of cuprate material. The invention also provides a high temperature superconductor (HTS) having a doped, nanoparticulate pinning structure including a plurality of layers of a cuprate material and a plurality of layers of a doped nanoparticulate pinning material. At least one layer of the doped nanoparticulate pinning material is stacked between two layers of the cuprate material.

Flux pinning of cuprate superconductors with nanoparticles

Porous ceramic superconductors having a film thickness over 0.5 microns are provided. The superconducting material is applied to a vicinal substrate and optionally nanoparticles are inserted to release local strain. The resultant superconductors exhibit improved Jc values compared to nonvicinal (flat) counterparts and those having no nanoparticles.

Porous ceramic high temperature superconductors and method of making same

A method for enhancing the flux pinning of a YBCO superconductor by substituting minute quantities of rare earth elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) or other deleterious elements (Sc, etc.) for Y in YBCO thin films is described. The method of the present invention enables enhanced flux pinning of the material while not significantly increasing the cost of the HIS material and can be used in all HTS deposition methods since it is not process dependent.

Minute doping for YBCO flux pinning

An AC-tolerant high temperature superconductor tape with transposed filaments having two layers of high temperature superconducting material with striations and corresponding filaments and an insulating layer positioned therebetween.

AC-tolerant HTS coated conductor with transposed filaments

Nanometer-sized non-superconducting particulates in superconductive REBCO films, where RE is a rare earth metal, for flux pinning enhancement and a method of forming are disclosed. A target with a second phase material sector portion and a superconductive material portion is used in a pulse laser deposition process to form films on substrates according to the present invention. The films consist of 10-20 nm-sized precipitates. In a 0.5 &#x3bc;m thick film, a transport critical current density (J)&#x3e;3 MA/cmat 77K in self-field was measured. In one embodiment, magnetization Jat 77 K and 65K showed significant improvements in a composite YBCO films with fine precipitates produced according to the present invention as compared to non-doped (standard) YBCO films (&#x3e;10 times increase at 9 T, 65 K).

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A superconductor coating inclusive, tape-like electrical conductor and windings using such conductor for magnets and electrical machines, etc. The described windings are suited for inclusion of successor superconductor materials such as yttrium barium copper oxide wherein magnetic flux related losses can potentially be excessive and preclude successful machine operation. Winding orientation and configuration of the conductor in an alternating current machine for lower losses are disclosed along with methods and apparatus for achieving the desired windings. Windings intended for differing locations within a machine of this type are made possible by the invention. Equations relating to magnetic losses incurred in such windings are also disclosed.

Machinery windings of yttrium barium copper oxide and related coated conductor

A method of manufacturing a high temperature superconductor is disclosed. The method includes depositing, by pulsed laser deposition, alternating layers of YBa Cu O (Y123) and Y BaCuO (Y211). The Y211 layers are characterized by a multiplicity of nanosized globular inclusions, effectively enhancing flux pinning and thus increasing current transport.

Method of manufacturing a high temperature superconductor

A method of depositing nanoparticles for flux pinning into a superconducting material is described. According to the method of the present invention, a target made of superconducting material and a substrate are placed in the deposition chamber of a pulsed laser deposition apparatus. A first, moderate vacuum level is established in the chamber and the target is irradiated with light from a pulsed, high energy laser. By virtue of the moderate vacuum level, the material ejected from the target is slowed sufficiently to agglomerate into nanoparticles having the same composition as the target material. These nanoparticles are deposited upon the substrate. A uniform layer of superconducting material is deposited on the substrate by evacuating the deposition chamber to a second, high vacuum level and performing the pulsed laser deposition process again. The nanoparticles thus deposited within the superconducting material act as a flux pinning mechanism.

Growing community of inventors

West Milton, OH, United States of America

Paul N Barnes