波动-响应关系作为在不平衡量子和经典流体中测试远程相关性
1Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA; Department of Physics and Institute for Fundamental Science, University of Oregon, Eugene, Oregon 97403, USA; and Materials Science Institute, University of Oregon, Eugene, Oregon 97403, USA.
Physical review. E
|May 17, 2024
概括
研究人员发现,在不平衡稳定状态下,波动-响应关系发生了变化. 这允许使用响应实验研究量子流体中的远程相关性,即使是在无碰撞状态下.
科学领域:
- 非平衡的统计力学.
- 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:
- 由于缺乏简单的波动分散定理,研究热力学平衡之外的系统具有挑战性.
- 没有平衡的稳定状态表现出在平衡系统中看不到的独特的相关性行为.
研究的目的:
- 为了确定不平衡稳定状态的修改波动响应关系.
- 在温度梯度下研究费米离子量子流体的远程相关性.
- 通过响应实验来探测这些相关性.
主要方法:
- 分析交流器相关函数及其与二线性响应函数的关系.
- 在水力动力学和无碰撞系统中比较经典和量子流体行为.
- 研究速度波动及其对相关性的影响.
主要成果:
- 对于处于不平衡稳定状态,温度梯度恒定的系统,建立了一个修改的波动响应关系.
- 这种关系将交流器相关函数与二线性响应连接起来,适用于量子和经典系统.
- 长距离相关性,类似于经典流体,在费米子量子流体中发现,持续到无碰撞状态,具有修改的奇点行为.
结论:
- 修改的波动响应关系为研究不平衡系统,特别是量子流体提供了一个新的工具.
- 响应实验可以探测长距离的相关性,在这种情况下,直接观察波动是困难的.
- 从水力动力转变为无碰撞模式的转变改变了速度波动和相关性奇点.
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