Transport and magnetic properties of La-doped CaFe$_2$As$_2$
  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. 
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 and X. H....
cond-mat.supr-con cond-mat.str-el