近日，加拿大阿尔伯塔大学的J. Maldaner及其研究小组与加拿大莱斯布里奇大学的S. Das等人合作并取得一项新进展。经过不懈努力，他们对利用氙光磁强计测试量子引力进行可行性分析。相关研究成果已于2024年3月19日在国际知名学术期刊《物理评论A》上发表。

该研究团队提出了一种基于光学磁强计在稀有气体同位素¹²⁹Xe中，进行量子引力实验搜索的灵敏度限制分析。该分析依赖于与大多数量子引力理论公式一致的一般不确定性原理模型，其中标准不确定性关系由动量线性的前阶修正项优化。反过来，这种修正改变了实验中浸入磁场中的自旋极化¹²⁹Xe原子的磁矩，从而导致它们的拉莫尔频率随速度变化，这是通过双光子激光光谱检测到的。

原子速度的热分布与多普勒效应相结合，通过扫描不同原子速度下的询问激光，研究团队成功寻找到了对应的拉莫尔频率变化。此项研究表明，目前的技术手段已能将领头阶量子引力修正的现有界限提升高达10⁷倍，且在不远的将来，随着技术能力的不断提升，这一界限有望再增加10²倍。

附：英文原文

Title: Feasibility analysis of a proposed test of quantum gravity via optical magnetometry in xenon

Author: J. Maldaner, M. Fridman, S. Das, G. Porat

Issue&Volume: 2024/03/19

Abstract: We present an analysis of the sensitivity limits of a proposed experimental search for quantum gravity, using an approach based on optical magnetometry in the noble gas isotope ¹²⁹Xe. The analysis relies on a general uncertainty principle model that is consistent with most formulations of quantum gravity theory, where the canonical uncertainty relations are modified by a leading-order correction term that is linear in momentum. In turn, this correction modifies the magnetic moment of the spin-polarized ¹²⁹Xe atoms that are immersed in a magnetic field in the proposed experiment, which results in a velocity-dependent variation of their Larmor frequency, that is detected via two-photon laser spectroscopy. The thermal distribution of atomic velocities, in conjunction with the Doppler effect, is used to scan the interrogating laser over different atomic velocities and search for a corresponding variation in their Larmor frequencies. We show that the existing bounds on the leading-order quantum gravity correction can be improved by 10⁷ with existing technology, where another factor of 10² is possible with near-future technical capabilities.

DOI: 10.1103/PhysRevA.109.032814

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.032814