YBa_(2)Cu_(3)O_(7‐x)(YBCO)thin films were prepared on LaAlO_(3)(LAO)substrates by a sol–gel method,and the epitaxial growth of Bi‐2212 thin films on YBCO thin films was investigated.Both YBCO and Bi_(2)Sr_(2)Ca1Cu_...YBa_(2)Cu_(3)O_(7‐x)(YBCO)thin films were prepared on LaAlO_(3)(LAO)substrates by a sol–gel method,and the epitaxial growth of Bi‐2212 thin films on YBCO thin films was investigated.Both YBCO and Bi_(2)Sr_(2)Ca1Cu_(2)O_(8)+δ(Bi‐2212)bilayer films exhibit good biaxial texture and superconducting properties.Afterward,a cross‐shaped Bi‐2212/YBCO heterostructure was fabricated,and its interfacial atomic arrangement and I‐V characteristics were analyzed.Atomic‐resolution STEM images obtained from a spherical‐aberration‐corrected transmission electron microscope show that two superconducting films exhibit a layered structure and the atoms inside the films are artfully arranged.Moreover,the order of the seven atomic layers between Bi‐2212 and YBCO layers with a thickness of about 1.32 nm is misarranged.Among them,the Y‐O layer of YBCO and the Sr‐O layer of Bi‐2212 share a CuO_(2) layer.The I‐V curves of Bi‐2212/YBCO bilayer films show that the seven misarranged atomic layers at Bi‐2212/YBCO interface acts as a barrier layer,which means that a Josephson junction can be fabricated using this interface characters.展开更多
基金supported by the National Natural Science Foundation of China(52172273 and 51672212)the Key Science and Technology Program of Shaanxi Province of China(No.2020zdzx04‐04‐02).
文摘YBa_(2)Cu_(3)O_(7‐x)(YBCO)thin films were prepared on LaAlO_(3)(LAO)substrates by a sol–gel method,and the epitaxial growth of Bi‐2212 thin films on YBCO thin films was investigated.Both YBCO and Bi_(2)Sr_(2)Ca1Cu_(2)O_(8)+δ(Bi‐2212)bilayer films exhibit good biaxial texture and superconducting properties.Afterward,a cross‐shaped Bi‐2212/YBCO heterostructure was fabricated,and its interfacial atomic arrangement and I‐V characteristics were analyzed.Atomic‐resolution STEM images obtained from a spherical‐aberration‐corrected transmission electron microscope show that two superconducting films exhibit a layered structure and the atoms inside the films are artfully arranged.Moreover,the order of the seven atomic layers between Bi‐2212 and YBCO layers with a thickness of about 1.32 nm is misarranged.Among them,the Y‐O layer of YBCO and the Sr‐O layer of Bi‐2212 share a CuO_(2) layer.The I‐V curves of Bi‐2212/YBCO bilayer films show that the seven misarranged atomic layers at Bi‐2212/YBCO interface acts as a barrier layer,which means that a Josephson junction can be fabricated using this interface characters.