一个远离平衡的单维斯气体的普遍动力学
Sebastian Erne1,2,3, Robert Bücker1,4, Thomas Gasenzer2,5
1Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Vienna, Austria.
Nature
|November 9, 2018
概括
研究人员在远离平衡的孤立量子系统中观察到普遍的缩放. 这一发现在一维的斯气体中为量子多体物理学中的宇宙动力学提供了关键的实验证据.
科学领域:
- 量子多体物理学
- 不平衡的量子力学
- 超冷的原子气体
背景情况:
- 了解远离平衡的量子系统是一个重大挑战.
- 理论模型预测了各种系统的普遍扩展,但实验证据很少.
- 这种普遍性可以将早期宇宙的现象与重离子碰撞和冷原子联系起来.
研究的目的:
- 在一个孤立的量子系统中实验性地证明普遍的缩放.
- 描述一个远离平衡的斯气体的时间演变.
- 为非平衡量子力学的普遍性类提供基础.
主要方法:
- 从3D超冷的Bose气体中通过强冷却灭生成一个单维的Bose气体.
- 观察隔离系统的时间演变动量分布.
- 分析低动量行为以确定通用缩放函数和指数.
主要成果:
- 证明了1D波斯气体在时间变化的动量分布中的通用缩放.
- 确定了一个独立于时间的通用函数和一个控制低动量的扩展指数.
- 观测到一种向低动量的浮现性保存量,导致准凝结物形成.
结论:
- 在一个孤立的量子多体系统中建立了普遍缩放动态的实验证据.
- 这项工作是将远离平衡的动态按普遍性分类的关键一步.
- 开辟了冷原子系统模拟早期宇宙等高能量现象的可能性.
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