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arXiv · 0804.4668

Size effects in the nonlinear resistance and flux creep in a virtual Berezinskii-Kosterlitz-Thouless state of superconducting films

A. Gurevich·V. M. Vinokur
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Abstract

We show that the size effects radically affect the electric field-current ($E-I$) relation of superconducting films. We calculate $E(J)$ due to thermally-activated hopping of single vortices driven by current $I$ across the film in a magnetic field $H$, taking into account interaction of free vortices with their antivortex images and peaks in the Meissner currents at the film edges. Unbinding of virtual vortex-antivortex pairs not only mimics the transport uniform BKT behavior, it can dominate the observed $E(J)$ and result in the field-dependent ohmic resistance at small $I$. We show that $E(I)$ can be tuned by changing the film geometry and propose experimental tests of this theory.

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A. Gurevich, V. M. Vinokur. 2008-04-29. Size effects in the nonlinear resistance and flux creep in a virtual Berezinskii-Kosterlitz-Thouless state of superconducting films. https://doi.org/10.1103/physrevlett.100.227007

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