Anisotropic Ginzburg-Landau scaling of Hc2 and transport properties of 112-type Ca0.8La0.2Fe0.98Co0.02As2 single crystal

作者：Xing, Xiangzhuo; Zhou, Wei; Zhou, Nan; Yuan, Feifei; Pan, Yongqiang; Zhao, Haijun; Xu, Xiaofeng; Shi, Zhixiang^*

来源：Superconductor Science and Technology, 2016, 29(5): 055005.

DOI：10.1088/0953-2048/29/5/055005

• Ca0.8La0.2Fe0.98Co0.02As2 single crystal
• upper critical field anisotropy
• magnetization
• Hall effect and magnetoresistance
• superconductivity

High-quality single crystal Ca0.8La0.2Fe0.98Co0.02As2 has been successfully synthesized using a self-flux method. The magnetization measurement reveals a second peak effect and high critical current density J(c) exceeding 2 x 10(6) A cm(-2) at 5 K (self-field). The upper critical field anisotropy was systematically studied by measuring the electrical resistivity under various magnetic fields and angles. The angle-dependent magnetoresistance, by choosing an appropriate anisotropy parameter within the framework of the anisotropic Ginzburg-Landau (AGL) theory, can be scaled onto one single curve. In the normal state, the negative Hall coefficient shows strong but nonmonotonic T-dependence through a minimum at similar to 175 K. Moreover, it is shown that the magnetoresistance apparently violates the semiclassical Kohler's rule below similar to 175 K but can be well scaled by the Hall angle instead. This suggests either a change of carriers with T or exotic anisotropic scattering in the system.

• 出版日期2016-5
• 单位东南大学; 杭州师范大学