在Floquet驱动的瑞德伯格原子中,高阶和分数离散时间晶体
Bang Liu1,2, Li-Hua Zhang1,2, Qi-Feng Wang1,2
1Key Laboratory of Quantum Information, University of Science and Technology of China, 230026, Hefei, Anhui, China.
Nature communications
|November 10, 2024
概括
研究人员通过实验观察了原子气体中的更高阶和分数离散时间晶体 (DTC). 这一突破使得探测物质的异常阶段,探索超出当前能力的复杂时间对称性成为可能.
科学领域:
- 量子多体物理学 量子多体物理学
- 非平衡的动力学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 离散时间晶体 (DTCs) 代表着被打破离散时间转换对称性的异常物质相.
- 理论研究已经探索了高阶和分数DTC,但实验观测方法仍然难以捉摸.
- 了解这些独特的阶段对于推进非平衡物理至关重要.
研究的目的:
- 开发和演示一种用于观察高阶和分数离散时间晶体的实验方法.
- 在可控制的系统中研究这些奇异阶段的行为和特征.
- 扩大量子多体系统中时间对称性的基本理解.
主要方法:
- 使用Floquet驱动的Rydberg原子气体作为实验平台.
- 在原子气体系统中开发新技术来探测更高阶和分数DTC.
- 观察系统响应和不同DTC订单之间的转换.
主要成果:
- 成功观察了多个高阶离散时间晶体,整数n值高达14.
- 检测到有非整数n值的分数离散时间晶体.
- 在这些过渡过程中,在相邻的整数DTC和研究的分数DTC之间展示过渡.
结论:
- 开发的实验方法提供了在量子多体系统中探测高阶和分数DTC的第一个方法.
- 这些发现扩大了关于非平衡动态和时间对称性断裂的基本知识.
- 这项工作为发现更复杂的时间对称性和奇特的量子相铺平了道路.
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