发表机构
University of Maryland; National Institute of Standards and Technology (NIST); University of Toronto; University of Nevada, Reno（马里兰大学; 美国国家标准与技术研究院; 多伦多大学; 内华达大学里诺分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
通过全同粒子碰撞中的交换对称性实现散射截面的对称保护相干控制，在锂-锂碰撞中展示了对最终态宇称的完全控制，适用于同核分子等体系。
AI 中文摘要
我们展示了全同粒子碰撞中的交换对称性能够实现总散射截面的对称保护相干控制。对于全同费米子，反对称化强制贡献散射通道的完全相位同步，产生最大控制可见度。对于全同玻色子，同步性仍然存在，但由于额外的交换（卫星）贡献，可见度降低。可区分粒子的碰撞缺乏这种对称性施加的相位锁定，导致较低的可控性和可见度。我们通过锂-锂碰撞的耦合通道量子散射计算阐明了这些原理，比较了$^{6}\mathrm{Li}$-$^{6}\mathrm{Li}$（全同费米子）、$^{7}\mathrm{Li}$-$^{7}\mathrm{Li}$（全同玻色子）和$^{6}\mathrm{Li}$-$^{7}\mathrm{Li}$（可区分）体系。此外，在全同粒子情况下，对称性强制同步使得在任何碰撞能量下都能完全控制最终态的宇称。该机制广泛适用于全同粒子碰撞，包括同核分子，对于这些分子，已有的方法——直流电场或微波屏蔽——无效或不可用。
英文摘要
We show that exchange symmetry in collisions of identical particles enables symmetry-protected coherent control of the total scattering cross section. For identical fermions, antisymmetrization enforces a common control phase among contributing channels within a given parity sector, yielding maximal control visibility. For identical bosons, phase-locking persists but with reduced visibility due to additional exchange (satellite) contributions. Collisions of distinguishable particles lack this symmetry-imposed phase-locking, leading to lower controllability and visibility. We elucidate these principles through coupled-channel quantum-scattering calculations for lithium-lithium collisions, comparing the $^{6}\mathrm{Li}{-}^{6}\mathrm{Li}$ (identical fermions), $^{7}\mathrm{Li}{-}^{7}\mathrm{Li}$ (identical bosons), and $^{6}\mathrm{Li}{-}^{7}\mathrm{Li}$ (distinguishable) systems. Furthermore, in the identical-particle cases, symmetry-enforced phase-locking enables full control over the parity of the final state even beyond the ultracold regime. This mechanism is broadly applicable to identical-particle collisions, including homonuclear molecules for which established approaches--DC electric fields or microwave shielding--are ineffective or unavailable.
Comments15 pages, 10 figures
