发表刊物：Physical Review Letters
关键字：Physical Review Letters 134, 18, 181801(2025) 轴子探索研究聚焦于基础物理领域几大核心难题的交叉方向，包括量子色动力学中的强 CP 问题、暗物质本质探究以及宇宙正反物质不对称性起源解析。探测轴子诱导的自旋相关相互作用，是寻找轴子的一种高效手段。但长期以来，该探测手段始终无法在轴子质量窗口范围内开展研究，核心瓶颈在于难以平衡两大需求：既要大幅抑制高极化自旋源的磁场泄漏，又要在分米级短距离内探测飞特斯拉量级的奇异物理信号。本文利用铁屏蔽型钐钴SmCo5自旋源，搭配自主设计的自补偿共磁强计，开展了轴子诱导的奇异自旋 - 自旋相互作用实验，并公布最新实验结果。通过采用复合屏蔽结构，我们实现了最高11个量级的磁场抑制效果。依托该技术，我们在轴子质量窗口内对电子 - 中子耦合强度划定了全新约束范围，相比以往实验上限提升了四个数量级；同时也给出了目前最严格的电子 - 质子耦合约束。 该研究方案不仅有望推动超越标准模型的新物理探索，还有望在生物、化学研究领域带来颠覆性应用。 The search for axions sits at the intersection of solving critical problems in fundamental physics, including the strong CP problem in QCD, uncovering the nature of dark matter, and understanding the origin of the Universe’s matter-antimatter asymmetry. The measurement of axion mediated spin-dependent interactions offers a powerful approach for axion detection. However, it has long been restricted to regions outside the “axion window” due to a significant trade-off: the need to effectively suppress the magnetic leakage from highly polarized spin sources while simultaneously detecting subfemtotesla level exotic physics signals at sub-decimeter-scale distances. In this work, we report new experimental results on axion mediated exotic spin-spin interactions using an iron-shielded SmCo5 spin source in combination with a specially designed self-compensation comagnetometer. Employing a composite shielding structure, we achieved a suppression of the magnetic field by up to 11 orders of magnitude. This enabled us to establish new constraints on the coupling between electrons and neutrons, improving previous experimental limits by up to 10 000 times within the axion window. Furthermore, we also set the strongest constraints on the coupling between electrons and protons. The proposed method holds substantial potential not only for advancing the search for new physics beyond the standard model but also for enabling transformative applications in biological and chemical research.
卷号：134