在一个超导体中,峰值效应模式中的两个并存的旋阶段
M Marchevsky1, M J Higgins, S Bhattacharya
1NEC Research Institute, Princeton, New Jersey 08540, USA. marchev@research.nj.nec.com
Nature
|February 24, 2001
概括
像NbSe2这样的超导体的峰值效应是由具有不同固定强度的两个共存的状物质相解释的. 这一阶段的共存驱动了一个由混乱驱动的过渡,解决了一个40年的.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 超导性研究研究超导性.
- 材料科学是一种材料科学.
背景情况:
- II型超导体在超导体到正常金属过渡的附近表现出一个关键的电流异常,称为峰值效应.
- 这种峰值效应,即临界电流在消失之前达到峰值,已经无法解释40年了.
研究的目的:
- 调查NbSe2.2中峰值效应的潜在机制.
- 为了可视化在阶段临界电流的实体空间分布.
主要方法:
- 使用扫描式空调大厅显微镜.
- 在NbSe2.2中可视化了关键电流的真实空间分布.
主要成果:
- 确定了两个不同的状物质阶段,具有不同的固定强度,在峰值效应状态中在宏观尺度上共存.
- 证明了这些相的组成和转变解释了历史效应和异常电压反应.
结论:
- 两个状物质相的共存是NbSe2.2中峰值效应的原因.
- 这种相位共存是混乱驱动的非热相位过渡的标志.
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