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Title: Controllable injector for local flux entry into superconducting films

Abstract

A superconducting flux injector (SFI) has been designed to allow for controlled injections of magnetic flux into a superconducting film from a predefined location along the edge. The SFI is activated by an external current pulse, here chosen to be 200 ms long, and it is demonstrated on films of Nb that the amount of injected flux is controlled by the pulse height. Examples of injections at two different temperatures where the flux enters by stimulated flux-flow and by triggered thermomagnetic avalanches are presented. The boundary between the two types of injection is determined and discussed. The SFI opens up for active use of phenomena which up to now have been considered hazardous for a safe operation of superconducting devices.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences and Engineering Division; Sao Paulo Research Foundation (FAPESP)
OSTI Identifier:
1333744
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Superconductor Science and Technology; Journal Volume: 29; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; flux avalanches; flux dynamics; thermomagnetic instabilities

Citation Formats

Carmo, D., Colauto, F., de Andrade, A. M. H., Oliveira, A. A. M., Ortiz, W. A., and Johansen, T. H. Controllable injector for local flux entry into superconducting films. United States: N. p., 2016. Web. doi:10.1088/0953-2048/29/9/095003.
Carmo, D., Colauto, F., de Andrade, A. M. H., Oliveira, A. A. M., Ortiz, W. A., & Johansen, T. H. Controllable injector for local flux entry into superconducting films. United States. doi:10.1088/0953-2048/29/9/095003.
Carmo, D., Colauto, F., de Andrade, A. M. H., Oliveira, A. A. M., Ortiz, W. A., and Johansen, T. H. 2016. "Controllable injector for local flux entry into superconducting films". United States. doi:10.1088/0953-2048/29/9/095003.
@article{osti_1333744,
title = {Controllable injector for local flux entry into superconducting films},
author = {Carmo, D. and Colauto, F. and de Andrade, A. M. H. and Oliveira, A. A. M. and Ortiz, W. A. and Johansen, T. H.},
abstractNote = {A superconducting flux injector (SFI) has been designed to allow for controlled injections of magnetic flux into a superconducting film from a predefined location along the edge. The SFI is activated by an external current pulse, here chosen to be 200 ms long, and it is demonstrated on films of Nb that the amount of injected flux is controlled by the pulse height. Examples of injections at two different temperatures where the flux enters by stimulated flux-flow and by triggered thermomagnetic avalanches are presented. The boundary between the two types of injection is determined and discussed. The SFI opens up for active use of phenomena which up to now have been considered hazardous for a safe operation of superconducting devices.},
doi = {10.1088/0953-2048/29/9/095003},
journal = {Superconductor Science and Technology},
number = 9,
volume = 29,
place = {United States},
year = 2016,
month = 7
}
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