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Updated: Sep 13, 2025

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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
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在量子多体系统中不可逆转性的理论
Takato Yoshimura1,2, Lucas Sá3
1All Souls College, Oxford OX1 4AL, United Kingdom.
Physical review. E
|August 1, 2025
概括
这项研究揭示了Ruelle-Pollicott (RP) 共振如何解释量子多体系统中不可逆转的放松. 混乱系统中的异常放松源于这些共振,而保存定律则抑制了它.
科学领域:
- 量子多体理论 量子多体理论
- 这是量子混沌.
- 统计力学 统计力学
背景情况:
- 调和单元动力学与不可逆转的放松是量子多体理论的一个关键挑战.
- 鲁埃尔-波利科特 (RP) 共振解释了古典和单粒子量子混沌系统中的放松,但对于多体系统来说是不发达的.
- 量子多体RP共振与不可逆性之间的联系需要进一步研究.
研究的目的:
- 研究量子多体鲁埃尔-波利科特 (RP) 共振在驱动不可逆转放松的出现和作用.
- 在一个范式性的Floquet量子电路模型中分析证明不可逆性的起源,即随机相模型 (RPM).
- 探索诸如保存定律和多体定位等因素对异常放松的影响.
主要方法:
- 将光谱形状因子与自相关函数联系起来.
- 在随机相模型 (RPM) 中通过将其合到局部环境来分析证明不可逆性.
- 计算自相对应函数的时间演变,消散形式因子和时间顺序之外的相关函数 (OTOC).
- 在RPM中确定确切的RP共振,并将其与操作员截断进行比较.
主要成果:
- 没有保存定律的通用多体格子系统显示所有量子多体RP共振汇聚在单元盘内.
- 在热力学极限中,单元量子图发展出一个无限的衰变RP共振塔,导致异常放松.
- 在OTOC中,RPM表现出两阶段的放松,第二阶段由领先的RP共振控制.
- 保存定律,多体局部化和非局部相互作用将领先的RP共振转移到单位圆上,抑制异常放松.
结论:
- RP共振为量子系统中的宏观放松提供了微观解释.
- 在单元盘内部的RP共振的融合是多体量子混乱和不可逆转性的标志.
- 了解RP共振对于探索量子混乱和向经典不可逆转性过渡至关重要.
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