近日，美国科罗拉多大学博尔德分校James K. Thompson团队报道了腔中动量态之间三体和四体相互作用的实现。相关论文于2025年11月27日发表在《科学》杂志上。

在凝聚态物理和量子传感领域，自旋哈密顿量通常依赖于材料或系综组分间的两体（pairwise）相互作用。然而，探索更普遍的n>2多体相互作用正引起日益浓厚的兴趣。

研究组利用高精细度光学腔内的激光冷却原子系综，实现了有效三体（n=3）哈密顿量相互作用。该体系中，两个原子动量态编码了赝自旋信息。通过施加两个耦合光场，诱导原子通过腔模交换光子，实现了虚拟六光子过程；其中低阶相互作用因相消干涉而被抑制。研究组还观测到由虚拟八光子过程介导的四体（n=4）相互作用特征。该方法或可扩展至多能级系统的三体相互作用，乃至更高阶相互作用。

附：英文原文

Title: Realization of three- and four-body interactions between momentum states in a cavity

Author: Chengyi Luo, Haoqing Zhang, Chitose Maruko, Eliot A. Bohr, Anjun Chu, Ana Maria Rey, James K. Thompson

Issue&Volume: 2025-11-27

Abstract: Spin Hamiltonians in condensed matter and quantum sensing typically utilize pairwise or two-body interactions between constituents in the material or ensemble. However, there is growing interest in exploring more general n-body interactions for n > 2. In this study, we realized an effective n = 3-body Hamiltonian interaction using an ensemble of laser-cooled atoms in a high-finesse optical cavity with the pseudospin

encoded by two atomic momentum states. We applied two dressing tones that induce the atoms to exchange photons via the cavity to realize a virtual six-photon process; lower-order interactions destructively interfered. We also observed signatures of a n = 4-body interaction mediated by a virtual eight-photon process. Our approach may be extensible to three-body interactions in multilevel systems or to even higher-order interactions.

DOI: adv0990

Source: https://www.science.org/doi/10.1126/science.adv0990