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Updated: Jul 8, 2025

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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
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通过Penning-Trap质谱仪在高电荷中观察低的超稳定电子状态
Kathrin Kromer1, Chunhai Lyu1, Menno Door1
1Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany.
Physical review letters
|December 15, 2023
概括
研究人员为下一代原子钟确定了高电荷离子 (HCI) 中的长寿命电子状态. 离子 (Pb^{41+}) 的这种超稳定状态具有精确测量的能量,为先进的时钟技术铺平了道路.
科学领域:
- 原子,分子和光学物理学
- 量子信息科学 量子信息科学
- 高能离子物理学 高能离子物理学
背景情况:
- 高电荷离子 (HCI) 呈现许多电子过渡,适合先进的原子钟研究.
- 极端紫外线频率便于在HCI中探索较短波长时钟过渡.
- 在没有对时钟状态能量的先验知识的情况下,在HCI中探测狭窄的过渡是具有挑战性的.
研究的目的:
- 实验观察和理论计算一个长期存在的电子状态在Nb-like Pb^{41+}中,作为一个潜在的时钟状态.
- 为了精确地确定这种元稳定状态的激发能量.
主要方法:
- 使用PENTATRAP质谱仪直接测量转稳态的激发能量作为质量差.
- 进行了ab initio多配置迪拉克-哈特里-福克计算,以确定状态的能量.
- 计算了已识别过渡的寿命和质量因子.
主要成果:
- 在Pb^{41+} 中的元稳态的激发能被确定为31.28) eV,分数不确定性为4×10^{-12}.
- 实验结果与理论计算 (31.68~13 eV和31.76~35 eV) 非常一致.
- 得到的计算寿命为26.5~5.3天,质量系数为1.1×10^{23}.
结论:
- 在Pb^{41+}中发现的超稳定状态是下一代HCI原子钟的有希望的候选者.
- 精确的能量测定和长寿命使得可以制造具有低于10^{-19}/sqrt[τ]的潜在分数频率不稳定的时钟.
- 这项工作推动了使用高电荷离子的超精确计时设备的开发.
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