Mehdi Zain, Haine Simon A, Hope Joseph J, Szigeti Stuart S
Department of Quantum Science and Technology and Department of Fundamental and Theoretical Physics, Research School of Physics, <a href="https://ror.org/019wvm592">Australian National University</a>, Canberra 2600, Australia.
Phys Rev Lett. 2024 Aug 16;133(7):073401. doi: 10.1103/PhysRevLett.133.073401.
We investigate the fundamental viability of cooling ultracold atomic gases with quantum feedback control. Our Letter shows that the trade-off between the resolution and destructiveness of optical imaging techniques imposes constraints on the efficacy of feedback cooling, and that rapid rethermalization is necessary for cooling thermal gases. We construct a simple model to determine the limits to feedback cooling set by the visibility of density fluctuations, measurement-induced heating, and three-body atomic recombination. We demonstrate that feedback control can rapidly cool high-temperature thermal clouds in quasi-2D geometries to degenerate temperatures with minimal atom loss compared to traditional evaporation. Our analysis confirms the feasibility of feedback cooling ultracold atomic gases, providing a pathway to new regimes of cooling not achievable with current approaches.
我们研究了利用量子反馈控制冷却超冷原子气体的基本可行性。我们的论文表明，光学成像技术的分辨率与破坏性之间的权衡对反馈冷却的效率施加了限制，并且快速再热化对于冷却热气体是必要的。我们构建了一个简单模型来确定由密度涨落的可见度、测量诱导加热和三体原子复合所设定的反馈冷却极限。我们证明，与传统蒸发相比，反馈控制能够在准二维几何结构中将高温热云快速冷却至简并温度，且原子损失最小。我们的分析证实了反馈冷却超冷原子气体的可行性，为当前方法无法实现的新冷却机制提供了一条途径。
