[论文解读] Tune-out wavelength for the thulium atom near 576 nm

Ivan Pyrkh, Arjuna Rudnev+13 more|arXiv (Cornell University)|Feb 24, 2026

Cold Atom Physics and Bose-Einstein Condensates被引用 0

一句话总结

该论文在理论上预测并在接近 576 nm 的基态镝（thulium）上进行实验测量，确认极化率的零点并在特定窄波长范围内实现玻色-爱因斯坦凝聚（BEC）

ABSTRACT

We report the theoretical prediction and measurement of a tune-out wavelength for the ground state of the thulium atom in a linearly polarized optical dipole trap with a wavelength of approximately 576 nm. The measurements were conducted using a combination of trap frequency and RF loss spectroscopy, thus making it possible to separate the scalar and tensor parts of the total polarizability without measurements in the range of negative total polarizability. The calculated tune-out wavelength is consistent with the measured one of $575.646_{-0.014}^{+0.016}$ nm in air. The existence of the zero in the polarizability for the Tm ground state was confirmed by the trap loss experiment, which also made it possible to refine the tune-out wavelength to $575.646_{-0.004}^{+0.004}$. Despite the presence of an imaginary part of the polarizability at some wavelengths, it was experimentally demonstrated that, with a proper choice of the dipole trap polarization, it was possible to achieve Bose-Einstein condensation of thulium atoms in the range from 575.348 to 575.689 nm, covering the tune-out wavelength.

研究动机与目标

• 在线性极化陷阱中辨识镝基态极化率为零的 tune-out 波长。
• 在不经过负极化率区间的前提下分离总极化率的标量与张量贡献。
• 用陷阱频率与射频损耗光谱验证预测的 tune-out 波长。
• 在 tune-out 点周围的窄波长范围内 refine tune-out 波长并展示 BEC。

提出的方法

• 将陷阱频率测量与射频损耗光谱结合以提取极化率分量。
• 在 576 nm 夹持中使用可分离标量与张量极化率的分析。
• 在偏振优化的偶极陷阱中展示镝的玻色-爱因斯坦凝聚。
• 将测得的 tune-out 波长与理论预测进行对比并 refine 值。

实验结果

研究问题

• RQ1 在线性极化陷阱中，接近 576 nm 的镝基态的 tune-out 波长是多少？
• RQ2 是否能够在不穿越负极化率区间的情况下分离总极化率的标量与张量分量？
• RQ3 极化率的零点是否在实验不确定度内出现，以及它与理论的一致性？
• RQ4 通过选择合适的极化，可以在包含 tune-out 波长的陷阱范围内实现镝的 BEC 吗？

主要发现

• 计算得到的 tune-out 波长与在空气中测得的值 575.646_{-0.014}^{+0.016} nm 一致。
• 陷阱损耗实验确认镝基态极化率存在零点。
• tune-out 波长 refined 为 575.646_{-0.004}^{+0.004} nm。
• 镝在从 575.348 到 575.689 nm 的偶极陷阱范围内实现了 BEC，覆盖 tune-out 波长。
• 对适当的偶极陷阱极化的选择可以在某些波长的极化率虚部存在时仍实现凝聚。