铁磁(La_(0.7)Ca_(0.3)MnO_3)/高温超导(YBa_2Cu_3O_7)双层薄膜微结构的高分辨电镜研究  

High resolution electron microscopy study of ferromagnet(La_(0.7)Ca_(0.3)MnO_3)/superconductor(YBa_2Cu_3O_7) bi-layer

作　　者：王明光[1] 徐奕辰[1] 祁阳[1] 王志嘉 

机构地区：[1]东北大学理学院,辽宁沈阳110004 [2]辽宁省分析科学研究院,辽宁沈阳110015

出　　处：《功能材料》2012年第15期2052-2055,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(51172040)

摘　　要：采用脉冲激光沉积法在LaAlO3(LAO)衬底上生长了YBa2Cu3O7/La0.7Ca0.3MnO3(YBCO/LC-MO)和La0.7Ca0.3MnO3/YBa2Cu3O7(LCMO/YBCO)两种外延薄膜,利用高分辨电子显微镜研究了其微观结构。在YBCO/LCMO/LAO薄膜中,LCMO以层-岛模式生长,并形成层状取向畴结构。YBCO层均由c轴取向晶粒组成,其中含有c/3平移畴界、额外CuO层及Y2O3第二相等缺陷结构。在LCMO/YBCO/LAO薄膜中,LAO衬底上初始生长的YBCO为c轴取向,至一定厚度(几个纳米)转为c与a轴混合生长。LCMO层在YBCO上外延生长并具有[100]m与[011]m混合取向畴结构。在LCMO/YBCO界面未观察到失配位错,因此二者界面属应变型界面。Epitaxial YBa2 Cu3O/La0.7 Ca0.3 MnO3 （YBCO/LCMO） and La0.7 Ca0.3 MnO3/YBa2 Cu3 07 （ LCMO/YB-CO） bi-layers were fabricated on LaA103 （LAO） substrate by pulsed laser deposition, and their microstructures were investigated by using high resolution electron microscopy. In YBCO/LCMO/LAO bi-layer, LCMO layer growed on LAO substrate with a layer-island mode, and developed a layered oriented domain structure. YBCO layers consisted of c-axis oriented domain. Some defects such as c/3 translational boundary, extra CuO layer and Y203 second phase were observed in YBCO film. In LCMO/YBCO/LAO hi-layer, the initial YBCO layer on LAO showed c-axis orientation, and switched to a mixed domain structure containing both c-axis and a-axis when the film thickness reached several nanometers. LCMO layer, which comprises a mixed domain of [100]m and [011]m orientation, epitaxially growed on YBCO film. No misfit dislocation was observed between LCMO and YBCO interface, which was characterized by a strain interface.

关 键 词：高分辨电子显微镜 取向畴 平移畴界 巨磁阻 薄膜 

分 类 号：O766[理学—晶体学]