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arXiv · 0806.1209

Superconductivity in hole-doped (Sr$_{1-x}$K$_x$)Fe$_2$As$_2$

G. F. Chen·Z. Li·G. Li·W. Z. Hu·J. Dong·X. D. Zhang·P. Zheng·N. L. Wang·J. L. Luo
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Abstract

A series of layered (Sr$_{1-x}$K$_x$)Fe$_2$As$_2$ compounds with nominal x=0 to 0.40 are synthesized by solid state reaction method. Similar to other parent compounds of iron-based pnictide superconductors, the pure SrFe$_2$As$_2$ shows a strong resistivity anomaly near 210 K, which was ascribed to the spin-density-wave instability. The anomaly temperature is much higher than those observed in LaOFeAs and BaFe$_2$As$_2$, the two prototype parent compounds with ZrCuSiAs- and ThCr$_2$Si$_2$-type structures. K-doping strongly suppresses this anomaly and induces superconductivity. Like in the case of K-doped BaFe$_2$As$_2$, sharp superconducting transitions at T$_c\sim$38 K was observed. We performed the Hall coefficient measurement, and confirmed that the dominant carriers are hole-type. The carrier density is enhanced by a factor of 3 in comparison to F-doped LaOFeAs superconductor.

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G. F. Chen, Z. Li, G. Li, W. Z. Hu, J. Dong, X. D. Zhang, P. Zheng, N. L. Wang, J. L. Luo. 2008-06-06. Superconductivity in hole-doped (Sr$_{1-x}$K$_x$)Fe$_2$As$_2$. https://arxiv.org/abs/0806.1209

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