发表机构
School of Electronics, Peking University; National Key Laboratory of Advanced Micro and Nano Manufacture Technology, School of Integrated Circuits, Peking University; Beijing Advanced Innovation Center for Integrated Circuits; Hefei National Laboratory（北京大学电子学院; 北京大学集成电路学院先进微纳制造技术国家重点实验室; 北京集成电路创新中心; 合肥国家实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出态相关扩散模型解释强驱动热原子光谱，通过速度矩展开推导闭合方程，实验验证反常光泵浦路径，实现高强下97%透射率，为抗饱和原子器件设计提供框架。
AI 中文摘要
我们提出了一种用于强驱动热原子光谱的态相关扩散模型。从单个原子的轨迹依赖内态演化出发，我们通过速度矩展开推导出局部密度矩阵场的闭合空间方程。对$^{85}$Rb原子滤光器透射光谱的测量与模型吻合良好，最大高斯峰值强度达$1.27\ imes10^{3}$ W/cm$^2$，接近$^{85}$Rb D2线饱和强度以上六个数量级。反直觉的是，该模型揭示了一种反常光泵浦路径，其中强光将原子从名义上的暗态转移到亮态。超精细帕邢-巴克分裂选择性地增强该反常路径，同时抑制常规光泵浦，使滤光器在所研究的最高强度下保持约97%的透射率。这项工作为控制强驱动原子系综和设计抗饱和原子光学器件提供了框架。
英文摘要
We propose a state-dependent diffusion model for strongly driven thermal-atom spectra. Starting from the trajectory-dependent internal-state evolution of individual atoms, we derive a closed spatial equation for the local density-matrix field using a velocity-moment expansion. Measurements of an $^{85}$Rb atomic-filter transmission spectrum agree well with the model up to a maximum Gaussian peak intensity of $1.27\times10^{3}$ W/cm$^2$, approaching six orders of magnitude above the $^{85}$Rb D2-line saturation intensity. Counterintuitively, the model reveals an anomalous optical-pumping pathway in which intense light transfers atoms from nominally dark states into bright states. Hyperfine Paschen--Back splitting selectively enhances this anomalous pathway while suppressing conventional optical pumping, allowing the filter to maintain approximately 97$\%$ transmission at the highest intensity studied. This work provides a framework for controlling strongly driven atomic ensembles and designing saturation-resistant atomic optical devices.
Comments9 pages, 4 figures
