Effect of Zn doping on magnetic order and superconductivity in LaFeAsO

Yuke Li, Xiao Lin, Qian Tao, Cao Wang, Tong Zhou, Linjun Li,Qingbo Wang, Mi He, Guanghan Cao1and Zhu’an Xu1

Department of Physics, Zhejiang University, Hangzhou 310027,People’s Republic of China 

E-mail:ghcao@zju.edu.cnandzhuan@zju.edu.cn

Abstract. 

We report Zn-doping effect in the parent and F-doped LaFeAsOoxy-arsenides. Slight Zn doping in LaFe1−xZnxAsO drastically suppresses theresistivity anomaly around 150 K associated with the antiferromagnetic (AFM)spin density wave (SDW) in the parent compound. The measurements ofmagnetic susceptibility and thermopower confirm further the effect of Zn dopingon AFM order. Meanwhile Zn doping does not affect or even enhances theTcofLaFe1−xZnxAsO0.9F0.1, in contrast to the effect of Zn doping in high-Tccuprates.We found that the solubility of Zn content (x) is limited to less than 0.1 in bothsystems and further Zn doping (i.e.x>0.1) causes phase separation. Our studyclearly indicates that the non-magnetic impurity of Zn2+ions doped in the Fe2As2layers affects selectively the AFM order and superconductivity remains robustagainst the Zn doping in the F-doped superconductors.

 https://iopscience.iop.org/article/10.1088/1367-2630/11/5/053008/pdf