Magnetic-flux quanta in superconducting thin films observed by electron holography and digital phase analysis
- Advanced Research Laboratory, Hitachi, Ltd., Hatoyama, Saitama 350-03, Japan (JP)
- Department of Electrical Engineering, Faculty of Engineering, Osaka University, Yamadaoka, Suita 565, (Japan)
Singly quantized magnetic fluxes in superconducting lead films have been directly observed in the form of magnetic-flux-line distributions by using an electron-holography technique. Combining this with the digital-phase-analysis method, we were able to determine the flux quantum {ital h}/2{ital e} for individual fluxes with a precision of {similar to}{ital h}/100{ital e}, and analyze the distributions of field-vector components around the fluxon centers. The internal-field distributions obtained were compared with those calculated from the Ginzburg-Landau equations with use of some models, and an overall agreement was found between them. We also observed the changes of the magnetic-flux structures of lead thin films as a function of their thickness. Fluxon pairs were observed in 0.2-{mu}m-thick films, which may correspond to those suggested by Kosterlitz-Thouless theory.
- OSTI ID:
- 5625282
- Journal Information:
- Physical Review, B: Condensed Matter; (USA), Vol. 43:10; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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