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arXiv · 0810.0986

Synthesis, structural and transport properties of the hole-doped Superconductor Pr_{1-x}Sr_xFeAsO

Gang Mu·Bin Zeng·Xiyu Zhu·Fei Han·Peng Cheng·Bing Shen·Hai-Hu Wen
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Abstract

Superconductivity was achieved in PrFeAsO by partially substituting Pr^{3+} with Sr^{2+}. The electrical transport properties and structure of this new superconductor Pr_{1-x}Sr_xFeAsO at different doping levels (x = 0.05$\sim$ 0.25) were investigated systematically. It was found that the lattice constants (a-axis and c-axis) increase monotonously with Sr or hole concentration. The superconducting transition temperature at about 16.3 K (95% $ρ_n$) was observed around the doping level of 0.20$\sim$ 0.25. A detailed investigation was carried out in the sample with doping level of x = 0.25. The domination of hole-like charge carriers in this material was confirmed by Hall effect measurements. The magnetoresistance (MR) behavior can be well described by a simple two-band model. The upper critical field of the sample with T_c = 16.3 K (x = 0.25) was estimated to be beyond 45 Tesla. Our results suggest that the hole-doped samples may have higher upper critical fields comparing to the electron-doped ones, due to the higher quasi-particle density of states at the Fermi level.

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Gang Mu, Bin Zeng, Xiyu Zhu, Fei Han, Peng Cheng, Bing Shen, Hai-Hu Wen. 2009-01-13. Synthesis, structural and transport properties of the hole-doped Superconductor Pr_{1-x}Sr_xFeAsO. https://doi.org/10.1103/physrevb.79.104501

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