<sup>6</sup>Li超冷费米气体宽Feshbach共振散射的动力学演化研究

张蓓; 李芳; 邓书金; 武海斌

doi:doi:10.3788/jqo20192504.0502

量子光学学报, 2019, 25 (4): 413, 网络出版: 2020-03-09

⁶Li超冷费米气体宽Feshbach共振散射的动力学演化研究

Study on Time-dependent Broad Feshbach Resonance Scattering in Ultracold Fermi Atoms of ⁶Li

论文大纲

张蓓 ^*李芳邓书金武海斌

作者单位

华东师范大学精密光谱科学与技术国家重点实验室，上海 200062

Feshbach共振超冷费米原子气体动力学演化 Feshbach resonance ultracold Fermi gases time-dependent dynamics

摘要

本文解析研究了6Li超冷费米气体宽Feshbach共振散射动力学演化过程，将整个散射过程转化为一个单重态和一系列准连续态的散射共振，等效于涉及接触势的散射过程，在原子波包的持续时间内，束缚态中不断地出现原子布居，并将输入的波包非弹性散射到与之耦合的所有通道中。随着相互作用时间的增加，布居数转移幅度越来越大，连续态和束缚态之间的散射概率逐步增加，最终达到碰撞稳态。同时我们定量的计算了在原子散射过程中连续态和束缚态的动力学演化，在散射过程中连续态和束缚态的总概率守恒，连续态和束缚态之间布局数交换发生在散射共振前后的数十纳秒时间内。

Abstract

In this paper,6Li we analytically studies the scattering dynamic evolution of broad Feshbach resonance scattering in 6Li ultracold Fermi gases. A time-dependent description is given of a scattering process involving a single resonance embedded in a set of flat continua, which is similar to the scattering process involving contact potential. During the duration of the atomic wave packet, the atom population appears continuously in the bound state, and the input wave packet is inelastic scattered to the coupled continuous channel. With the increasing of the interaction time, the population transferring becomes faster, and the scattering probability between the continuous state and the bound state keeps rising to the collisional steady state. At the same time, we quantitatively calculate the dynamic evolution of continuous and bound states in the process of atom scattering. We find the total probability of continuous and bound states is no surprisedly conserved, and the population exchange between continuous and bound states takes place within tens of nanoseconds during the scattering process.

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张蓓, 李芳, 邓书金, 武海斌. ⁶Li超冷费米气体宽Feshbach共振散射的动力学演化研究[J]. 量子光学学报, 2019, 25(4): 413. ZHANG Bei, LI Fang, DENG Shu-jin, WU Hai-bin. Study on Time-dependent Broad Feshbach Resonance Scattering in Ultracold Fermi Atoms of ⁶Li[J]. Acta Sinica Quantum Optica, 2019, 25(4): 413.

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