多伦多大学研究小组与格里菲斯大学量子动力学中心的研究人员通过实验验证，光子通过原子云时出现的"负停留时间"不仅是理论幻想，而是具有可测量的物理效应[1]。研究人员采用极弱激光束进行测量，通过检测光束相位的微小变化来探测原子激发状态，发现原子确认了光子所经历的相同负停留时间[1]。
负停留时间不能通过"只有光脉冲前端通过原子云"的解释来说明，这进一步证实了该现象的真实性[1]。由于需要平均运行数百万次实验才能获得准确的停留时间测量值，这项工作的完成技术难度颇高[1]。相关研究成果已于2026年8月4日发表在《物理评论快报》第136卷第15期上[1]。
Researchers have experimentally confirmed that the "negative dwell time" observed when photons pass through a cloud of atoms represents a genuine physical effect rather than a mere computational artifact.[1] Through weak measurements performed on the atoms themselves, scientists discovered that the atoms confirmed the identical negative dwell time measured for the photons, demonstrating that this quantum mechanical phenomenon reflects an authentic physical reality despite not violating standard physics.[1]
The study, published in Physical Review Letters (2026; 136 (15)), employed an extremely weak laser beam to detect atomic excitation by measuring minute phase changes in the light beam.[1] The measurement required averaging results across millions of experimental runs to obtain accurate dwell time values.[1] Crucially, the observed negative dwell time cannot be explained by the theory that only the leading edge of the light pulse interacts with the atomic cloud.[1]
The research was conducted by teams at the University of Toronto and the Center for Quantum Dynamics at Griffith University.[1]