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arXiv · 0909.2740

Bulk Superconductivity at 2.6 K in Undoped RbFe_2As_2

Z. Bukowski·S. Weyeneth·R. Puzniak·J. Karpinski·B. Batlogg
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Abstract

The iron arsenide RbFe_2As_2 with the ThCr_2Si_2-type structure is found to be a bulk superconductor with T_c=2.6 K. The onset of diamagnetism was used to estimate the upper critical field H_c2(T), resulting in dH_c2/dT=-1.4 T/K and an extrapolated H_c2(0)=2.5 T. As a new representative of iron pnictide superconductors, superconducting RbFe_2As_2 contrasts with BaFe_2As_2, where the Fermi level is higher and a magnetic instability is observed. Thus, the solid solution series (Rb,Ba)Fe_2As_2 is a promising system to study the crossover from superconductivity to magnetism.

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Z. Bukowski, S. Weyeneth, R. Puzniak, J. Karpinski, B. Batlogg. 2009-09-15. Bulk Superconductivity at 2.6 K in Undoped RbFe_2As_2. https://doi.org/10.1016/j.physc.2009.11.103

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