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arXiv · 1005.3989

Microscopic Study of the Superconducting State of the Iron Pnictide RbFe_2As_2

Z. Shermadini·J. Kanter·C. Baines·M. Bendele·Z. Bukowski·R. Khasanov·H. -H. Klauss·H. Luetkens·H. Maeter·G. Pascua·B. Batlogg·A. Amato
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Abstract

A study of the temperature and field dependence of the penetration depth λof the superconductor RbFe_2As_2 (T_c=2.52 K) was carried out by means of muon-spin rotation measurements. In addition to the zero temperature value of the penetration depth λ(0)=267(5) nm, a determination of the upper critical field B_c2(0)=2.6(2) T was obtained. The temperature dependence of the superconducting carrier concentration is discussed within the framework of a multi-gap scenario. Compared to the other "122" systems which exhibit much higher Fermi level, a strong reduction of the large gap BCS ratio 2Δ/k_B T_c is observed. This is interpreted as a consequence of the absence of interband processes. Indications of possible pair-breaking effect are also discussed.

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Z. Shermadini, J. Kanter, C. Baines, M. Bendele, Z. Bukowski, R. Khasanov, H. -H. Klauss, H. Luetkens, H. Maeter, G. Pascua, B. Batlogg, A. Amato. 2010-05-28. Microscopic Study of the Superconducting State of the Iron Pnictide RbFe_2As_2. https://doi.org/10.1103/physrevb.82.144527

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