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arXiv · 2001.10151

Evolution of superconductivity and antiferromagnetic order in Ba(Fe$_{0.92-x}$Co$_{0.08}$V$_x$)$_2$As$_2$

Jieming Sheng·Xingguang Li·Congkuan Tian·Jianming Song·Xin Li·Guangai Sun·Tianlong Xia·Jinchen Wang·Juanjuan Liu·Daye Xu·Hongxia Zhang·Xin Tong·Wei Luo·Liusuo Wu·Wei Bao·Peng Cheng
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Abstract

The vanadium doping effects on superconductivity and magnetism of iron pnictides are investigated in Ba(Fe$_{0.92-x}$Co$_{0.08}$V$_x$)$_2$As$_2$ by transport, susceptibility and neutron scattering measurements. The doping of magnetic impurity V causes a fast suppression of superconductivity with T$_c$ reduced at a rate of 7.4~K/1\%V. On the other hand, the long-range commensurate $C$-type antiferromagnetic order is recovered upon the V doping. The value of ordered magnetic moments of Ba(Fe$_{0.92-x}$Co$_{0.08}$V$_x$)$_2$As$_2$ follows a dome-like evolution versus doping concentration x. A possible Griffiths-type antiferromagnetic region of multiple coexisting phases in the phase diagram of Ba(Fe$_{0.92-x}$Co$_{0.08}$V$_x$)$_2$As$_2$ is identified, in accordance with previous theoretical predictions based on a cooperative behavior of the magnetic impurities and the conduction electrons mediating the Ruderman-Kittel-Kasuya-Yosida interactions between them.

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Jieming Sheng, Xingguang Li, Congkuan Tian, Jianming Song, Xin Li, Guangai Sun, Tianlong Xia, Jinchen Wang, Juanjuan Liu, Daye Xu, Hongxia Zhang, Xin Tong, Wei Luo, Liusuo Wu, Wei Bao, Peng Cheng. 2020-01-28. Evolution of superconductivity and antiferromagnetic order in Ba(Fe$_{0.92-x}$Co$_{0.08}$V$_x$)$_2$As$_2$. https://doi.org/10.1103/physrevb.101.174516

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