发表机构
Université de Bordeaux-IOGS-CNRS; University of Trento（波尔多大学; 特伦托大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对冷原子实验中离子泵杂散磁场的问题，提出在标准离子泵上添加反向辅助永磁体与集成软磁蜂窝状场阻挡器的组合配置，可显著降低外部磁场，同时控制抽速损失。
AI 中文摘要
冷原子实验中使用的离子泵会产生杂散磁场，该磁场可干扰磁光俘获、移动塞曼敏感能级，并在精密光谱学中引入系统误差。我们数值研究了一种紧凑的低杂散场离子泵配置，旨在在不增大泵整体尺寸的情况下减少通过超高真空（UHV）端口的磁通量泄漏。从标准离子泵的简化磁模型出发，我们研究了两种互补的改进方案：在原有泵磁体周围添加磁化方向相反的辅助永磁体，以及在泵端口集成软磁蜂窝状场阻挡器。所得组合配置大幅降低了泵外部的磁通量密度。在本文所考虑的几何结构中，距UHV端口10 mm处的磁场降低了97.9%，而蜂窝状阻挡器导致的有效抽速计算降低值为17.9%。这些结果表明，经设计的磁补偿和场引导结构可在保持抽气性能的同时，支持更紧凑的冷原子真空系统。进一步的工作应通过非线性静磁建模、分子流模拟以及完整泵几何结构的测量来验证该设计。
英文摘要
Ion pumps used in cold-atom experiments generate stray magnetic fields that can perturb magneto-optical trapping, shift Zeeman sensitive energy levels, and introduce systematic errors in precision spectroscopy. We numerically investigate a compact low-stray-field ion pump configuration designed to reduce magnetic flux leakage through the ultrahigh-vacuum port without increasing the overall pump size. Starting from a simplified magnetic model of a standard ion pump, we study two complementary modifications: auxiliary permanent magnets surrounding the original pump magnets with opposite magnetisation, and a soft-magnetic honeycomb field stopper integrated at the pump port. The resulting combined configuration strongly reduces the magnetic flux density outside the pump. In the geometry considered here, the field at 10 mm from the UHV port is reduced by 97.9%, while the calculated reduction in effective pumping speed due to the honeycomb stopper is 17.9%. These results indicate that engineered magnetic compensation and field-guiding structures can support more compact cold-atom vacuum systems while preserving pumping performance. Further work should validate the design with nonlinear magnetostatic modelling, molecular-flow simulations, and measurements on a complete pump geometry.
Comments8 pages, 5 figures, 2 tables
