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arXiv · 0902.0997

Type-1.5 Superconductors

V. V. Moshchalkov·M. Menghini·T. Nishio·Q. H. Chen·A. V. Silhanek·V. H. Dao·L. F. Chibotaru·N. D. Zhigadlo·J. Karpinsky
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Abstract

We demonstrate the existence of a novel superconducting state in high quality two-component MgB2 single crystalline superconductors where a unique combination of both type-1 (kappa_1 < 0.707) and type-2 (kappa_2 > 0.707) superconductor conditions is realized for the two components of the order parameter. This condition leads to a vortex-vortex interaction attractive at long distances and repulsive at short distances, which stabilizes unconventional stripe- and gossamer-like vortex patterns that we have visualized in this type-1.5 superconductor using Bitter decoration and also reproduced in numerical simulations.

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V. V. Moshchalkov, M. Menghini, T. Nishio, Q. H. Chen, A. V. Silhanek, V. H. Dao, L. F. Chibotaru, N. D. Zhigadlo, J. Karpinsky. 2009-02-19. Type-1.5 Superconductors. https://doi.org/10.1103/physrevlett.102.117001

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