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arXiv · 1906.08706

Enhancement of penetration field in vortex nanocrystals due to Andreev bound states

M. I. Dolz·N. R. Cejas Bolecek·J. Puig·H. Pastoriza·G. Nieva·J. Guimpel·C. J. van der Beek·M. Konczykowski·Y. Fasano
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Abstract

We study the penetration field $H_{\rm P}$ for vortex nanocrystals nucleated in micron-sized samples with edges aligned along the nodal and anti-nodal directions of the d-wave superconducting parameter of Bi$_2$Sr$_2$CaCu$_2$O$_{8 - δ}$. Here we present evidence that the $H_{\rm P}$ for nanocrystals nucleated in samples with edges parallel to the nodal direction is larger than for the antinodal case, $\sim 72$\,\% at low temperatures. This finding supports the theoretical proposal that surface Andreev bound states appearing in a sample with edges parallel to the nodal direction would produce an anomalous Meissner current that increases the Bean-Livingston barrier for vortex penetration.This has been detected thanks to the nucleation of vortex nanocrystals with a significant surface-to-volume ratio.

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M. I. Dolz, N. R. Cejas Bolecek, J. Puig, H. Pastoriza, G. Nieva, J. Guimpel, C. J. van der Beek, M. Konczykowski, Y. Fasano. 2019-06-20. Enhancement of penetration field in vortex nanocrystals due to Andreev bound states. https://doi.org/10.1103/physrevb.100.064508

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