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arXiv · 0812.4520

Superconductivity in CeO_{1-x}F_xFeAs with upper critical field of 94 T

J. Prakash·S. J. Singh·S. Patnaik·A. K. Ganguli
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Abstract

We have successfully synthesized Ce based oxypnictide with fluorine doping (CeO_{1-x}F_xFeAs) by a two step solid state reaction method. Detailed XRD and EDX confirm the crystal structure and chemical compositions. We observe that an extremely high Hc2(0) of 94 T can be achieved in the x = 0.1 composition. This increase in Hc2(0) is accompanied by a decrease in transition temperature (38.4 K in x = 0.1 composition) from 42.5 K for the x = 0.2 phase. The in-plane Ginzburg-Landau coherence length is estimated to be ~ 27 A at x = 0.2 suggesting a moderate anisotropy in this class of superconductors. The Seebeck coefficient confirms the majority carrier to be electrons and strong dominance of electron-electron correlations in this multiband superconductor.

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J. Prakash, S. J. Singh, S. Patnaik, A. K. Ganguli. 2008-12-24. Superconductivity in CeO_{1-x}F_xFeAs with upper critical field of 94 T. https://doi.org/10.1016/j.physc.2008.11.008

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