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arXiv · 1001.2199

Scanning SQUID microscopy of vortex clusters in multiband superconductors

Taichiro Nishio·Vu Hung Dao·Qinghua Chen·Liviu F. Chibotaru·Kazuo Kadowaki·Victor V. Moshchalkov
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Abstract

In type-1.5 superconductors, vortices emerge in clusters, which grow in size with increasing magnetic field. These novel vortex clusters and their field dependence are directly visualized by scanning SQUID microscopy at very low vortex densities in MgB2 single crystals. Our observations are elucidated by simulations based on a two-gap Ginzburg-Landau theory in the type-1.5 regime.

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Taichiro Nishio, Vu Hung Dao, Qinghua Chen, Liviu F. Chibotaru, Kazuo Kadowaki, Victor V. Moshchalkov. 2010-01-13. Scanning SQUID microscopy of vortex clusters in multiband superconductors. https://doi.org/10.1103/physrevb.81.020506

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