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arXiv · 1202.3589

Transport and magnetic properties of La-doped CaFe$_2$As$_2$

J. J. Ying·J. C. Liang·X. G. Luo·X. F. Wang·Y. J. Yan·M. Zhang·A. F. Wang·Z. J. Xiang·G. J. Ye·P. Cheng·X. H. Chen
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Abstract

We measured the transport properties and susceptibility of single crystals Ca$_{1-x}$La$_x$Fe$_2$As$_2$(x=0, 0.05, 0.1, 0.15, 0.19 and 0.25). Large in-plane resistivity anisotropy similar to that in Co-doped 122 iron-pnictides is observed although no transition metals were introduced in the FeAs-plane. The in-plane resistivity anisotropy gradually increases with La doping below T$_{SDW}$, being different from the hole-doped 122 superconductors. The susceptibilities of the samples show that La doping leads to suppression of SDW and induces a Curie-Weiss-like behavior at low temperature, which is much stronger than the other 122 iron-based superconductors.

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J. J. Ying, J. C. Liang, X. G. Luo, X. F. Wang, Y. J. Yan, M. Zhang, A. F. Wang, Z. J. Xiang, G. J. Ye, P. Cheng, X. H. Chen. 2012-02-16. Transport and magnetic properties of La-doped CaFe$_2$As$_2$. https://doi.org/10.1103/physrevb.85.144514

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