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Updated: Jun 26, 2025
10:42
Preparing an Isotopically Pure 229Th Ion Beam for Studies of 229mTh
Published on: May 3, 2019
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激光激发Th-229核的激发过程
J Tiedau1, M V Okhapkin1, K Zhang1
1Physikalisch-Technische Bundesanstalt, 38116 Braunschweig, Germany.
Physical review letters
|May 17, 2024
概括
科学家们成功地使用可调节激光激发了-229 (Th-229) 中的8.4 eV核同位素. 这一突破使Th-229核激光光谱学和光学核钟的开发成为可能.
科学领域:
- 核物理 核物理 核物理
- 量子光学是一种量子光学.
- 材料科学 材料科学 材料科学
背景情况:
- -229 (Th-229) 核具有8.4 eV的同位体状态,这是已知的最低能量核激发状态.
- 这种独特的核能水平是开发光学核钟等新技术的有希望的候选人.
- 直接激发这种同位素一直是一个重要的实验挑战.
研究的目的:
- 为了实现Th-229中的8.4 eV核同位素的共振激发.
- 在固态宿主中描述Th-229同位素的光谱特性.
- 为Th-229核激光光谱和光学核钟奠定基础.
主要方法:
- 使用桌面调节激光系统来准Th-229同位素的特定能量转换.
- 使用多化 (Th:CaF_{2}) 晶体,其度不同.
- 观察了共振光作为检测信号,并用Th-232进行了控制实验.
主要成果:
- 在Th:CaF_{2}晶体中成功观察了共振光信号,证实了Th-229同位素的共振激发.
- 测量了核共振波长在148.3821(5) 纳米和频率在2020.409(7) THz.
- 在晶体中确定光寿命为630(15) 秒,在真空中产生1740(50) 秒的异构体半衰期.
结论:
- 通过激光技术证明了使用激光技术对Th-229核同位素进行共振激发的可行性.
- 这些测量参数对于推进Th-229核激光光谱学的发展至关重要.
- 这项研究代表了实现基于Th-229同位素的高精度光学核钟的重要一步.
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