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Steps in the Negative-Differential-Conductivity Regime of a Superconductor

Milind N. Kunchur·B. I. Ivlev·J. M Knight
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Abstract

Current-voltage characteristics were measured in the mixed state of Y1Ba2Cu3O(7-delta) superconducting films in the regime where flux flow becomes unstable and the differential conductivity dj/dE becomes negative. Under conditions where its negative slope is steep, the j(E) curve develops a pronounced staircase like pattern. We attribute the steps in j(E) to the formation of a dynamical phase consisting of the succesive nucleation of quantized distortions in the local vortex velocity and flux distribution within the moving flux matter.

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Milind N. Kunchur, B. I. Ivlev, J. M Knight. 2002-04-27. Steps in the Negative-Differential-Conductivity Regime of a Superconductor. https://doi.org/10.1103/physrevlett.87.177001

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