Enhancing superconductivity of ultrathin YBa2Cu3O7-δ films by capping non-superconducting oxides

Enhancing superconductivity of ultrathin YBa₂Cu₃O_7-δ films by capping non-superconducting oxides

Bo Hai¹, Ren Tianshuang¹, Chen Zheng¹, Zhang Meng¹, Xie Yanwu^{1, 2, †}

(a) The dependence of resistance on temperature for 5-uc YBCO films capped with different oxides. The thickness of all the capping layers is around 7 nm. The result of the uncapped YBCO is also shown for comparison (the dashed line). The inset replots the result of the uncapped and the LaAlO₃-capped samples in the linear coordinates. (b) The critical temperature, T_c, generated from the R–T curves shown in panel (a). Here, T_c is defined as the transition onset that is determined as the position of the maximum of the derivative curve, d R ( T ) / d T . The postannealing time for all these samples is 30 minutes.