在多体能量层次交叉处的ergodicity破裂,平衡和非热化
1Coordination of Physics, Federal Institute of Sergipe, Lagarto-SE 49400-975, Brazil.
Physical review. E
|September 19, 2023
概括
这项研究揭示了多粒子系统中热化分解的独特机制. 退化的能量水平可以导致持续的不平衡,如磁化,即使在平衡状态.
科学领域:
- 量子力学就是量子力学.
- 统计力学就是统计力学.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 许多粒子系统往往向平衡和热化发展.
- 了解非平衡动力学对于基础物理和技术应用至关重要.
- 能量水平交叉 (退化) 可以显著改变系统行为.
研究的目的:
- 分析一个多粒子系统的时间演变,从一个非平衡状态开始,在一个退化时有一个固定的控制参数.
- 为了研究在哪些条件下发生或崩的ergodicity,平衡和thermalization.
- 为了确定破解 Eigenstate 热化假设的新机制.
主要方法:
- 许多粒子系统的理论分析.
- 证明有关ergodicity,平衡和热化的定理.
- 研究具有对称等价基态和平价性考虑的系统.
- 哈伯德哈密尔顿模型的应用.
主要成果:
- 在某些条件下在平衡状态下持久的证明非能量性.
- 确定了特定的初始状态和退化的固态的非零时间平均左右粒子数不平衡.
- 展示了一个受青的基础状态的子空间,该系统最有可能居住在哪里.
- 插图显示了哈伯德模型中的ergodicity破坏,导致磁化失衡而不影响导电.
结论:
- 退化固态可以作为非热性固态,表明固态热化假设的弱分解.
- 观察到的非能量性和不平衡为量子系统动力学提供了独特的视角.
- 这些发现对利用受控量子状态的技术应用有潜在的影响.
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