概括
大量YBa2Cu3O7-delta超导体的高缺陷密度不能解释与薄膜相比较的低临界电流密度. 需要进一步的研究来了解这些YBCO材料中的流量固定差异.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 超导电性 超导电性 超导电性
背景情况:
- 批量YBa2Cu3O7-delta (YBCO) 超导体通过融纹理加工,显示出高位移密度 (10^910^10 cm−2).
- Y2BaCuO5内含物的分散增加了YBCO中低角度粒边界密度,距离在700 nm以下.
研究的目的:
- 研究批量YBCO超导体中缺陷密度和临界电流密度之间的关系.
- 为了比较散装YBCO中的缺陷水平与高临界电流薄膜中的缺陷水平.
- 了解大批量YBCO中限制流量固定强度的因素.
主要方法:
- 散装YBa2Cu3O7-delta. 的融化质感
- 扫描道显微镜 (STM) 用于缺陷分析.
- 在77K和1T时测量关键电流密度.
主要成果:
- 大量YBCO的缺陷密度与高临界电流薄膜的缺陷密度相当.
- 大量YBCO显示的临界电流密度为~10^4A/cm2在77K和1T,比薄膜低两个数量级.
- 在散装Y-Ba-Cu-O的超导体阶段观察到螺旋状的生长模式.
结论:
- 仅仅高缺陷密度并不能解释与薄膜相比,散装YBCO的临界电流密度降低.
- 散装和薄膜YBCO之间的流量固定强度差异不仅仅是由观察到的缺陷密度解释的.
- 需要进一步调查,以确定控制散装YBCO材料中的流量固定的主要机制.
相关概念视频
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