安德里耶夫的磁感受性在超流体状态下受到约束 ^{3}He-B
J W Scott1, M D Nguyen1, D Park1
1Northwestern University, Evanston, Illinois 60208, USA.
Physical review letters
|August 11, 2023
概括
核磁共振测量显示,空气凝中的超流体-3具有异常的磁性易感性. 这种异常表明表面安德里耶夫结合状态,不预期的库珀对行为,在低温下占主导地位.
科学领域:
- 低温物理 低温物理
- 凝聚物质物理学 凝聚物质物理学
- 量子流体是一种量子流体.
背景情况:
- 超流体-3呈现出复杂的相位,具有独特的磁性.
- 气凝封闭引入异构和表面效应,可能改变超流体的行为.
- 了解这些相互作用是探索新型量子现象的关键.
研究的目的:
- 为了研究超流体-3的磁性易感性,在异性气凝中吸入.
- 为了识别低温阶段,并分析偏离预期的磁性行为.
- 探索表面安德里耶夫结合状态在观察到的异常中的作用.
主要方法:
- 进行了核磁共振 (NMR) 测量.
- 测量了超流体-3的磁性易感性在异性气凝中.
- 分析频率变化以确定超流体相.
主要成果:
- 核磁共振测量显示,在低温下存在异常的磁性敏感性.
- 超流体-3的B相通过频率转移被确定.
- 观察到的敏感性并没有像预期的那样降低库珀对形成,这表明存在异常.
- 这种异常符合Ising-like表面Andreev束状态的预测高场行为.
结论:
- 空气凝中的超流体-3中的磁感应异常归因于表面安德里耶夫结合状态.
- 这些状态在平面气凝结构中表现出类似于Ising的磁性特征.
- 这些发现挑战了对有限超流体库珀对行为传统理解.
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