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arXiv · 0907.1308

Phase diagram of the PrFeAsO$_{1-x}$F$_{x}$ superconductor

C. R. Rotundu·D. T. Keane·B. Freelon·S. D. Wilson·A. Kim·P. N. Valdivia·E. Bourret-Courchesne·R. J. Birgeneau
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Abstract

The electronic phase diagram of PrFeAsO$_{1-x}$F$_{x}$ (0$\leq$x$\leq$0.225) has been determined using synchrotron X-ray powder diffraction, magnetization and resistivity measurements. The structural transition temperature is suppressed from 154 K to $\approx$120 K and the magnetic phase transitions of both iron and praseodymium ions are completely suppressed by x$\approx$0.08 fluorine doping, coinciding with the emergence of superconductivity. The optimal doping is x$\approx$0.15 when T$_{C}$=47 K, while the maximum solubility of fluorine in PrFeAsO$_{1-x}$F$_{x}$ is reached around x=0.22. The structural, magnetic and superconducting phase diagram is presented.

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C. R. Rotundu, D. T. Keane, B. Freelon, S. D. Wilson, A. Kim, P. N. Valdivia, E. Bourret-Courchesne, R. J. Birgeneau. 2009-07-07. Phase diagram of the PrFeAsO$_{1-x}$F$_{x}$ superconductor. https://doi.org/10.1103/physrevb.80.144517

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