近日，加拿大英属哥伦比亚大学的Roman V. Krems及其研究团队取得一项新进展。经过不懈努力，他们揭示原子-原子散射热碰撞的普适性边界。相关研究成果已于2024年12月16日在国际知名学术期刊《物理评论A》上发表。

该研究团队采用严格的量子散射计算，研究了原子-原子碰撞的热平均速率系数对相互作用势变化的响应。通过将量子散射观测值视为由相互作用势分布决定的概率预测，研究人员对速率系数的普适性及其边界进行了全面分析。

研究发现，由此得出的速率系数分布存在一个特征变化，这一变化将轻的、少电子原子与重的、可极化原子区分开来。研究人员绘制了图示，展示了不同温度下热碰撞普适性的边界，并为未来旨在利用这种普适性的实验提供了指导。

据悉，人们观察到，某些原子碰撞的热速率系数在短程原子间相互作用的细节上表现出惊人的独立性。这使得这些速率系数成为长程相互作用参数和质量的通用函数，这一特性此前已被用于开发一种用于环境压力测量的自定义原子传感器。

附：英文原文

Title: Boundaries of universality of thermal collisions for atom-atom scattering

Author: Xuyang Guo, Kirk W. Madison, James L. Booth, Roman V. Krems

Issue&Volume: 2024/12/16

Abstract: Thermal rate coefficients for some atomic collisions have been observed to be remarkably independent of the details of interatomic interactions at short range. This makes these rate coefficients universal functions of the long-range interaction parameters and masses, which was previously exploited to develop a self-defining atomic sensor for ambient pressure. Here we employ rigorous quantum scattering calculations to examine the response of thermally averaged rate coefficients for atom-atom collisions to changes in the interaction potentials. We perform a comprehensive analysis of the universality, and the boundaries thereof, by treating the quantum scattering observables as probabilistic predictions determined by a distribution of interaction potentials. We show that there is a characteristic change of the resulting distributions of rate coefficients, separating light, few-electron atoms, and heavy polarizable atoms. We produce diagrams that illustrate the boundaries of the thermal collision universality at different temperatures and provide guidance for future experiments seeking to exploit the universality.

DOI: 10.1103/PhysRevA.110.063317

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.063317