Tracking Evaporative Cooling of a Mesoscopic Atomic Quantum Gas in Real Time
Tracking Evaporative Cooling of a Mesoscopic Atomic Quantum Gas in Real Time
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DOI：
10.1103/physrevx.11.041017
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发表时间：
2020-12
影响因子：
12.5
通讯作者：
J. Zeiher;Julian Wolf;J. Isaacs;Jonathan Kohler;D. Stamper-Kurn
中科院分区：
文献类型：
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作者：
J. Zeiher;Julian Wolf;J. Isaacs;Jonathan Kohler;D. Stamper-Kurn
随着组成粒子数量的减少，多体系统中热力学和输运特性的波动变得越来越重要。超冷原子气体为介观系统的研究提供了干净的环境；然而，时间波动的检测受到典型破坏性检测的阻碍，无法对同一样品进行重复精确测量。在这里，我们通过利用光学腔中增强的光-物质耦合来执行微创连续测量并跟踪准二维原子气体在从倾斜捕获势蒸发期间原子数的时间演化，从而克服了这一限制。我们证明了足够的测量精度来检测远低于泊松统计设定水平的原子数波动。此外，从实时测量中获得的原子数的两次相关性揭示了蒸发过程的非线性以及控制原子从捕获体积中传输的噪声源。我们的研究结果建立了耦合原子腔系统作为观察介观冷原子气体中的热力学和输运现象的新型测试平台，并为原子量子模拟器原子数和温度的腔辅助反馈稳定铺平了道路。
The fluctuations in thermodynamic and transport properties in many-body systems gain in importance as the number of constituent particles is reduced. Ultracold atomic gases provide a clean setting for the study of mesoscopic systems; however, the detection of temporal fluctuations is hindered by the typically destructive detection, precluding repeated precise measurements on the same sample. Here, we overcome this limitation by utilizing the enhanced light-matter coupling in an optical cavity to perform a minimally invasive continuous measurement and track the time evolution of the atom number in a quasi two-dimensional atomic gas during evaporation from a tilted trapping potential. We demonstrate sufficient measurement precision to detect atom number fluctuations well below the level set by Poissonian statistics. Furthermore, two-time correlations of the atom number obtained from the real-time measurements shed light on the non-linearity of the evaporation process and the noise sources governing the transport of atoms out of the trapping volume. Our results establish coupled atom-cavity systems as a novel testbed for observing thermodynamics and transport phenomena in mesosopic cold atomic gases and pave the way for cavity-assisted feedback stabilization of atom number and temperature of atomic quantum simulators.