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Updated: Jan 30, 2026

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Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
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固态-229核钟的频率可重现性
Tian Ooi1, Jack F Doyle1, Chuankun Zhang1
1JILA, NIST and University of Colorado, Department of Physics, University of Colorado, Boulder, CO, USA.
Nature
|January 28, 2026
概括
固态-229 (229Th) 核钟提供了增强的精度计量技术. 研究人员描述了229Th:CaF2核时钟过渡,为未来的紧时钟找到最佳的温度和高频率可重复性.
科学领域:
- 核物理 核物理 核物理
- 计量学 计量学 计量学
- 固态物理 固态物理
背景情况:
- 固态-229 (229Th) 核钟正在成为精密计量学和基本物理研究的强大工具.
- 它们对环境因素的敏感性较低,以及固态晶体中高发射密度的可能性,与当前的原子钟相比,它们具有优势.
- 固态系统只需要简单的热控制,对于开发紧的,可在现场部署的时钟至关重要.
研究的目的:
- 探索和描述229Th:CaF2核时钟过渡的频率可重现性.
- 为了研究兴奋剂度,温度和时间对过渡的线宽和中心频率的影响.
- 在固态宿主中建立控制229Th连贯核激发的基础.
主要方法:
- 在不同的兴奋剂度,温度和时间的变化下,测量过渡线宽和中心频率.
- 对度依赖的同质线宽的表征,鉴别因宿主晶体内在性质造成的局限性.
- 确定一个最佳工作温度 (196(5) K),其中第一阶段的热灵敏性消失.
主要成果:
- 报告了核过渡的度依赖的不均线宽,受到CaF2晶体特性的限制.
- 确定了1965K的最佳工作温度,在这种温度下,一级热灵敏度变得可以忽略不计.
- 在195K时,两个不同合的229Th:CaF2晶体在七个月内获得了220Hz (1.1 × 10^-13分数不确定性) 的频率可重现性.
结论:
- 该研究为理解和控制229Th在固态宿主中的连贯核激发提供了基础数据.
- 确定了最佳温度和实现的可重现性,为开发高度稳定,紧的核钟铺平了道路.
- 这些进步有可能用于限制基本常数的时间变化和增强精度计量学的应用.
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