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Updated: May 14, 2026
Niobium Oxide Films Deposited by Reactive Sputtering: Effect of Oxygen Flow Rate
Published on: September 28, 2019
AC conductivity of a niobium thin film in a swept magnetic field
M I Tsindlekht1, V M Genkin, S Gazi
1The Racah Institute of Physics, The Hebrew University of Jerusalem, 91904 Jerusalem, Israel. mtsindl@vms.huji.ac.il
Abstract:
We report results of measurements of the ac conductivity of a Nb superconducting thin film in a swept dc magnetic field. In the mixed state the swept dc field creates vortices at the film surface which pass through the film and form the observed ac conductivity. Vortex rate generation does not depend on the value of the dc field and there is a large plateau-like region of dc magnetic fields where the dissipation is approximately constant. A proposed phenomenological model describes quite well the main features of the ac response in these fields, including its dependency on the sweep rate, ac amplitude, frequency, and value of the second and third harmonics.
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