Combined effect of nanorod and stacking fault for improving nanorod interface in YBa2Cu3O7-δ nanocomposite films
Combined effect of nanorod and stacking fault for improving nanorod interface in YBa2Cu3O7-δ nanocomposite films
复制标题
纳米棒和堆垛层错的联合作用改善YBa2Cu3O7-δ纳米复合薄膜中纳米棒界面
DOI：
10.1088/1361-6668/abaebf
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发表时间：
2020
影响因子：
3.6
通讯作者：
Matsumoto Kaname
中科院分区：
文献类型：
--
作者：
Horide Tomoya;Ishimaru Manabu;Sato Kazuhisa;Matsumoto Kaname
YBa 2Cu 3 O 7− δ薄膜中的自组织纳米棒是重要的钉扎中心。虽然已经详细讨论了纳米尺度因素（> 4-5 nm）对涡旋钉扎的影响，但是还没有进行纳米棒的界面控制（在较小尺度下）。在这里，它表明，堆垛层错可以控制纳米棒的界面，以改善涡旋钉扎。通过对含有BaMO 3（M= Zr，Sn，Hf）纳米棒的YBa 2 Cu 3 O 7− δ薄膜进行后退火，在纳米棒上形成了层错。YBa 2 Cu 3 O 7− δ和BaMO 3之间的强键合改变了YBa 2 Cu 3 O 7− δ的原子位置，降低了界面的清晰度和纳米棒的基本钉扎力。扫描透射电子显微镜和密度泛函理论计算表明，层错破坏了YBa 2Cu 3 O 7-δ和BaMO 3之间在纳米棒界面的强键合，降低了纳米棒周围的局部应变，提高了基元钉扎力。结果表明，当磁场沿c轴方向时，低温低磁场下的临界电流密度得到提高。因此，纳米夹杂物和晶体缺陷（在本情况下，纳米棒和堆垛层错）的组合效应可以控制纳米夹杂物钉扎中心的界面，打开界面设计以实现理想的钉扎情况。
Self-organized nanorods in YBa 2 Cu 3 O 7− δ films are important pinning centers from the technical and fundamental views. While influence of nanoscale factors (> 4–5 nm) on the vortex pinning has already been discussed in detail, the interface control of nanorods (at the smaller scale) has not yet been performed. Here, it is demonstrated that the stacking faults can control the nanorod interface to improve the vortex pinning. The stacking faults were formed across the nanorods by post-annealing the YBa 2 Cu 3 O 7− δ films containing BaMO 3 (M= Zr, Sn, Hf) nanorods. The strong bonding between YBa 2 Cu 3 O 7− δ and BaMO 3 varies the atomic position of YBa 2 Cu 3 O 7− δ, degrading an interface sharpness and an elementary pinning force of the nanorod. Scanning transmission electron microscopy and density functional theory calculation clarified that the stacking faults broke the strong bonding between YBa 2 Cu 3 O 7− δ and BaMO 3 at the nanorod interface, and reduced the local strain around the nanorods, improving the elementary pinning force. As a result, the critical current density was improved in low temperature and low magnetic field when magnetic field was aligned with the c-axis. Thus, the combined effect of nanoinclusions and crystalline defects, in the present case, nanorods and stacking faults, can control the interface of nanoinclusion pinning centers, opening the interface design to realize the ideal pinning situation.