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Direct Observation of Vortex Shells and Magic Numbers in Mesoscopic Superconducting Disks

I. V. Grigorieva·L. Y. Vinnikov·W. Escoffier·J. Richardson·S. V. Dubonos·V. Oboznov·A. K. Geim
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Abstract

We have visualised and studied vortex configurations in mesoscopic superconducting disks using the Bitter decoration technique. For a broad range of vorticities L the circular geometry is found to result in the formation of concentric shells of vortices. From images obtained on disks of different sizes in a range of magnetic fields we were able to trace the evolution of vortex states and identify stable and metastable configurations. Furthermore, quantitative analysis of shell filling with increasing L allowed us to identify 'magic' numbers corresponding to the appearance of consecutive new shells.

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I. V. Grigorieva, L. Y. Vinnikov, W. Escoffier, J. Richardson, S. V. Dubonos, V. Oboznov, A. K. Geim. 2005-06-24. Direct Observation of Vortex Shells and Magic Numbers in Mesoscopic Superconducting Disks. https://doi.org/10.1103/physrevlett.96.077005

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