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arXiv · 1012.4440

Observation of Multi-Gap Superconductivity in GdO(F)FeAs by Andreev Spectroscopy

T. E. Shanygina·Ya. G. Ponomarev·S. A. Kuzmichev·M. G. Mikheev·S. N. Tchesnokov·O. E. Omel'yanovskii·A. V. Sadakov·Yu. F. Eltsev·A. S. Dormidontov·V. M. Pudalov·A. S. Usol'tsev·E. P. Khlybov
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Abstract

We have studied current-voltage characteristics of Andreev contacts in polycrystalline GdO$_{0.88}$F$_{0.12}$FeAs samples with bulk critical temperature ${T_c}$ = (52.5 \pm 1)K using break-junction technique. The data obtained cannot be described within the single-gap approach and suggests the existence of a multi-gap superconductivity in this compound. The large and small superconducting gap values estimated at T = 4.2K are {\Delta}L = 10.5 \pm 2 meV and {\Delta}S = 2.3 \pm 0.4 meV, respectively.

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T. E. Shanygina, Ya. G. Ponomarev, S. A. Kuzmichev, M. G. Mikheev, S. N. Tchesnokov, O. E. Omel'yanovskii, A. V. Sadakov, Yu. F. Eltsev, A. S. Dormidontov, V. M. Pudalov, A. S. Usol'tsev, E. P. Khlybov. 2010-12-20. Observation of Multi-Gap Superconductivity in GdO(F)FeAs by Andreev Spectroscopy. https://doi.org/10.1134/s0021364011020111

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