ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
We describe a magnetic induction probe capable of rapid measurement of the critical current densities of superconducting thin films in a noncontacting, nondestructive fashion. The use of an iron core enables us to generate field levels at the sample surface of 4000 A/cm (0.5 T) and thereby to measure a critical current density of 8×107 A/cm2 in a film 0.5-μm thick. The technique provides the ability to measure a current-voltage relationship without contacting the film and, thereby, to establish criteria for the definition of a critical current. We discuss the design, operation, and calibration of the device. The probe has proven effective in evaluating YBa2Cu3Ox (YBCO) thin films. We observe evidence of "flux creep'' in YBCO films and "flux jumps'' in Nb and NbCN films.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1143146
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