Cayado Pablo, Li Minjuan, Erbe Manuela, Liu Zhiyong, Cai Chuanbing, Hänisch Jens, Holzapfel Bernhard
Karlsruhe Institute of Technology (KIT), Institute for Technical Physics (ITEP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
Shanghai Key Laboratory of High Temperature Superconductors, Physics Department, Shanghai University, Shanghai 200444, People's Republic of China.
R Soc Open Sci. 2020 Nov 18;7(11):201257. doi: 10.1098/rsos.201257. eCollection 2020 Nov.
The main objective of this work was to study the superconducting properties of BCO films with a mixture of rare-earth () ions with large difference in ion size, in particular Sm and Yb. These Yb Sm BaCuO films have been successfully prepared for the first time by chemical solution deposition following the extremely low-fluorine route, which allows reducing the fluorine content by 93% with respect to standard full trifluoroacetate solutions. On the one hand, critical temperature remains stable at approximately 90 K with Sm content up to = 0.5 where starts to increase towards the values of pure SmBCO films of approximately 95 K. On the other hand, the critical current densities of the pure SmBCO films are the largest at 77 K, where the influence of a higher is very relevant, while at lower temperatures and low fields, the mixed films reach larger values. This demonstrates that mixing rare-earth elements in BaCuO causes a change in the pinning properties of the films and reveals the importance of selecting adequate BCO compounds according to the temperature and magnetic field region of a desired application.
这项工作的主要目标是研究含有离子尺寸差异较大的稀土（）离子混合物，特别是钐（Sm）和镱（Yb）的铋系铜氧化物（BCO）薄膜的超导性能。这些Yb-Sm-BaCuO薄膜首次通过极低氟路线的化学溶液沉积法成功制备，与标准的全三氟乙酸盐溶液相比，该方法可使氟含量降低93%。一方面，临界温度在钐含量高达=0.5时保持在约90 K稳定，此后开始向纯SmBCO薄膜约95 K的值增加。另一方面，纯SmBCO薄膜的临界电流密度在77 K时最大，此时较高的影响非常显著，而在较低温度和低磁场下，混合薄膜达到更大的值。这表明在BaCuO中混合稀土元素会导致薄膜钉扎性能的变化，并揭示了根据所需应用的温度和磁场区域选择合适的BCO化合物的重要性。
