Superconductivity in Sm-doped CaFe<sub>2</sub>As<sub>2</sub> single crystals

Superconductivity in Sm-doped CaFe₂As₂ single crystals

Chen Dong-Yun¹, Ruan Bin-Bin¹, Yu Jia¹, Guo Qi¹, Wang Xiao-Chuan¹, Mu Qing-Ge¹, Pan Bo-Jin¹, Liu Tong¹, Chen Gen-Fu^{1, 2}, Ren Zhi-An^{1, 2, †,}

(a) The temperature dependence of normalized resistivity between 2 K and 60 K under different magnetic fields for a Ca_0.8Sm_0.2Fe₂As₂ single crystal. (b) The upper critical field μ₀H_c2 determined by resistive curves with three different criteria: 90%, 50%, and 10% of normal state resistivity, and the solid lines represent the fitting results with two-band model.