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arXiv · 0804.1582

Pressure Effects on the Superconducting and Spin-Density-Wave States of the Newly Discovered Sm(O1-xFx)FeAs

B. Lorenz·K. Sasmal·R. P. Chaudhury·X. H. Chen·R. H. Liu·T. Wu·C. W. Chu
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Abstract

High temperature superconductors with a Tc above 40 K have been found to be strongly correlated electron systems and to have a layered structure. Guided by these rules, Kamihara et al. discovered a Tc up to 26 K in the layered La(O1-xFx)FeAs. By replacing La with tri-valence rare-earth elements RE of smaller ionic radii, Tc has subsequently been raised to 41-52 K. Many theoretical models have been proposed emphasizing the important magnetic origin of superconductivity in this compound system and a possible further Tc-enhancement in RE(O1-xFx)FeAs by compression. This later prediction appears to be supported by the pressure-induced Tc-increase in La(O0.89F0.11)FeAs observed. Here we show that, in contrast to previous expectations, pressure can either suppress or enhance Tc, depending on the doping level, suggesting that a Tc exceeding 50's K may be found only in the yet-to-be discovered compound systems related to but different from R(O1-xFx)FeAs and that the Tc of La(O1-xFx)FeAs and Sm(O1-xFx)FeAs may be further raised to 50's K.

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B. Lorenz, K. Sasmal, R. P. Chaudhury, X. H. Chen, R. H. Liu, T. Wu, C. W. Chu. 2008-08-04. Pressure Effects on the Superconducting and Spin-Density-Wave States of the Newly Discovered Sm(O1-xFx)FeAs. https://arxiv.org/abs/0804.1582

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