State-to-state chemistry for three-body recombination in an ultracold rubidium gas
State-to-state chemistry for three-body recombination in an ultracold rubidium gas
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DOI：
10.1126/science.aan8721
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发表时间：
2017-11
期刊：
影响因子：
56.9
通讯作者：
Joschka Wolf;M. Deiss;A. Krükow;E. Tiemann;B. Ruzic;Yujun Wang;J. D’Incao;P. Julienne;J. Denschlag
中科院分区：
文献类型：
--
作者：
Joschka Wolf;M. Deiss;A. Krükow;E. Tiemann;B. Ruzic;Yujun Wang;J. D’Incao;P. Julienne;J. Denschlag
追踪三个穿过分子束的Rb原子提供了几十年的知识，让人们了解量子力学是如何控制化学反应的。尽管如此，这项技术通常仅限于两个伙伴的碰撞。Wolf等人。关于具有全量子态分辨率的三体过程的报告。通过在光学陷阱中将Rb原子冷却到超低温，他们能够观察到通过与第三个原子碰撞而稳定的二聚体的形成，并提取出产物状态与所涉及原子的初始状态的精确依赖关系。科学，这个问题页921在超冷温度下用量子力学解释了导致双原子Rb的三个原子的碰撞。对所有反应物和产物进行全量子态分辨的化学反应的实验研究一直是一个长期的挑战。在这里，我们制备了反应物的超冷少体量子态，并展示了三个自旋极化的超冷Rb(Rb)原子复合形成弱结合Rb2分子的态对态化学。测量的产品分布覆盖了大约90%的最终产品，我们能够区分出能级分裂小到20兆赫乘以普朗克常数的产品状态。此外，我们制定了产品分布的倾向规则，并开发了一个理论模型，该模型预测了我们的许多实验观察。该方案可以很容易地适用于其他物种，并为详细研究非弹性或反应过程打开了一扇门。
Tracking a trio of rubidium atoms Crossed molecular beams have provided decades' worth of knowledge into how quantum mechanics governs chemical reactivity. Nonetheless, the technique is generally limited to the collision of two partners. Wolf et al. report on a three-body process with full quantum state resolution. By cooling rubidium atoms to ultralow temperatures in an optical trap, they were able to observe dimer formation, stabilized by collision with a third atom, and extract the precise dependence of product states on the initial states of the atoms involved. Science, this issue p. 921 A three-atom collision leading to diatomic rubidium is elucidated quantum mechanically at ultracold temperature. Experimental investigation of chemical reactions with full quantum state resolution for all reactants and products has been a long-term challenge. Here we prepare an ultracold few-body quantum state of reactants and demonstrate state-to-state chemistry for the recombination of three spin-polarized ultracold rubidium (Rb) atoms to form a weakly bound Rb2 molecule. The measured product distribution covers about 90% of the final products, and we are able to discriminate between product states with a level splitting as small as 20 megahertz multiplied by Planck’s constant. Furthermore, we formulate propensity rules for the distribution of products, and we develop a theoretical model that predicts many of our experimental observations. The scheme can readily be adapted to other species and opens a door to detailed investigations of inelastic or reactive processes.