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Enhancement of Pinning Energy and Critical Current Density in Tl2CaBa2Cu2O8 Films by Proton Irradiation

Published online by Cambridge University Press:  28 February 2011

M. E. Reeves
Affiliation:
Naval Research Laboratory, Code 6344, Washington D.C. 20375–5000
B. D. Weaver
Affiliation:
Naval Research Laboratory, Code 6344, Washington D.C. 20375–5000
G. P. Summers
Affiliation:
Naval Research Laboratory, Code 6344, Washington D.C. 20375–5000 Department of Physics, University of Maryland, Baltimore County, Baltimore, MD 21228
R. J. Soulen Jr
Affiliation:
Naval Research Laboratory, Code 6344, Washington D.C. 20375–5000
W. L. Olson
Affiliation:
Superconducting Technologies, Inc., 460 Ward Dr., Santa Barbara, CA, 93111–2310 presently at Motorola AIEG, 4000 Commercial Ave., Northbrook, II 60062
M. M. Eddy
Affiliation:
Superconducting Technologies, Inc., 460 Ward Dr., Santa Barbara, CA, 93111–2310
T. W. James
Affiliation:
Superconducting Technologies, Inc., 460 Ward Dr., Santa Barbara, CA, 93111–2310
E. J. Smith
Affiliation:
Superconducting Technologies, Inc., 460 Ward Dr., Santa Barbara, CA, 93111–2310
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Abstract

Measurements are presented which show the effect of proton irradiation on the irreversibility line and critical current in Tl2 CaBa2Cu2O8 thin films. These data show that the irreversibility line is dependent on the defect structure and that the pinning energy is increased by proton irradiation. This leads to an increase in the critical current density at 60 K for the lowest radiation dose. Further irradiation reduces the critical current, even while the irreversibility line is enhanced.

Type
Research Article
Copyright
Copyright © Materials Research Society 1992

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References

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