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Metastability and uniqueness of vortex states at depinning

Mahesh Chandran·R. T. Scalettar·G. T. Zimanyi
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Abstract

We present results from numerical simulations of transport of vortices in the zero-field cooled (ZFC) and the field-cooled (FC) state of a type-II superconductor. In the absence of an applied current $I$, we find that the FC state has a lower defect density than the ZFC state, and is stable against thermal cycling. On the other hand, by cycling $I$, surprisingly we find that the ZFC state is the stable state. The FC state is metastable as manifested by increasing $I$ to the depinning current $I_{c}$, in which case the FC state evolves into the ZFC state. We also find that all configurations acquire a unique defect density at the depinning transition independent of the history of the initial states.

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Mahesh Chandran, R. T. Scalettar, G. T. Zimanyi. 2004-04-16. Metastability and uniqueness of vortex states at depinning. https://doi.org/10.1103/physrevlett.89.187001

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