Superconductivity with peculiar upper critical fields in quasi-one-dimensional Cr-based pnictides |
(color online) (a) Resistive superconducting transitions in polycrystals of A2Cr3As3 (A =K, Rb, Cs). The inset shows the close-up. (b) Superconducting transition in electrical resistivity (with current flowing along the c-axis direction) for K2Cr3As3 single crystals. The inset shows the derivative of resistivity, defining |