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arXiv · 1410.7418

Detection of discretized single-shell penetration in mesoscopic vortex matter

Moira Inés Dolz·Yanina Fasano·Néstor René Cejas Bolecek·Hernán Pastoriza·Marcin Konczykowski·Cornelius Jacominus van der Beek
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Abstract

We investigated configurational changes in mesoscopic vortex matter with less than thousand vortices during flux penetration in freestanding 50 $μ$m diameter disks of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8 +δ}$. High-resolution AC and DC local magnetometry data reveal oscillations in the transmittivity echoed in peaks in the third-harmonics magnetic signal fainting on increasing vortex density. By means of extra experimental evidence and a simple geometrical analysis we show that these features fingerprint the discretized entrance of single-shells of vortices having a shape that mimics the sample edge.

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Moira Inés Dolz, Yanina Fasano, Néstor René Cejas Bolecek, Hernán Pastoriza, Marcin Konczykowski, Cornelius Jacominus van der Beek. 2014-10-27. Detection of discretized single-shell penetration in mesoscopic vortex matter. https://arxiv.org/abs/1410.7418

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