近日，美国芝加哥大学的Zhiqiang Wang及其研究团队取得一项新进展。经过不懈努力，他们揭示窄费什巴赫共振附近原子-分子超流体的稳定性和动力学。相关研究成果已于2024年7月11日在国际知名学术期刊《物理评论A》上发表。

据悉，最近对玻色子原子凝聚形成的稳定分子凝聚物和相关的“超化学”动力学的观察引发了一系列有趣的问题。

该研究团队深入探究了原子分子超流体中这种出乎意料的稳定性和动力学的微观机制。他们发现，这些现象背后的一个关键因素是在19.849G处¹³³Cs展现出的一个极窄的费什巴赫共振。通过理论与实验的对比分析，研究人员阐明了这种窄共振如何能够动态地催生出一个大的闭通道分子分数超流体，且该现象出现在幺正性附近。

从理论上讲，观察到的超化学现象（即原子和分子的玻色增强反应）被证实是由具有相反动量的类库珀玻色子原子对的形成所辅助的。尤为重要的是，这种窄共振为探索分子玻色超流体的量子临界点和相关现象提供了新的可能性，这在更典型的宽费什巴赫共振附近是无法实现的。

附：英文原文

Title: Stability and dynamics of atom-molecule superfluids near a narrow Feshbach resonance

Author: Zhiqiang Wang, Ke Wang, Zhendong Zhang, Shu Nagata, Cheng Chin, K. Levin

Issue&Volume: 2024/07/11

Abstract: The recent observations of a stable molecular condensate emerging from a condensate of bosonic atoms and related “super-chemical” dynamics have raised an intriguing set of questions. Here we provide a microscopic understanding of this unexpected stability and dynamics in atom-molecule superfluids; we show one essential element behind these phenomena is an extremely narrow Feshbach resonance in  ¹³³Cs   at 19.849G. Comparing theory and experiment, we demonstrate how this narrow resonance enables the dynamical creation of a large closed-channel molecular fraction superfluid, appearing in the vicinity of unitarity. Theoretically, the observed superchemistry (i.e., Bose-enhanced reactions of atoms and molecules) is found to be assisted by the formation of Cooper-like pairs of bosonic atoms that have opposite momenta. Importantly, this narrow resonance opens the possibility to explore the quantum critical point of a molecular Bose superfluid and related phenomena which would not be possible near a more typically broad Feshbach resonance.

DOI: 10.1103/PhysRevA.110.013306

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.013306