在 ^{9}Be^{+} 中使用单个被困离子测量D线的绝对频率
D M Fairbank1, A L Banducci1, R W Gunkelman1
1Department of Physics, Colorado State University, Fort Collins, Colorado 80523, USA.
Physical review letters
|September 18, 2023
概括
研究人员精确测量了^{9}Be^{+} D线过渡的光学频率,在被困离子中实现了电偶极允许过渡的记录精度. 这一进步改善了原子光谱学和基本物理学的理解.
科学领域:
- 原子物理 原子物理
- 量子光学是一种量子光学.
- 频谱学是一种光谱学.
背景情况:
- 被困离子实验对于高精度测量至关重要.
- 电二极允许 (E1) 过渡提供了有价值的原子结构信息.
- 之前对^{9}Be^{+}D线的测量在精度上有局限性.
研究的目的:
- 用前所未有的精度测量D线过渡的光学频率在^{9}Be^{+}中.
- 为了提高原子光谱学对被困离子的精度.
- 为了提取基本的原子参数,如细结构分裂和超细常数.
主要方法:
- 使用一个单个激光冷却的离子储存在无线电频率保罗陷中.
- 采用了一种光谱激光器,该激光器被稳定到光学频率.
- 通过NIST,将测量值转换为协调普世时间 (UTC).
- 仔细考虑了光子反弹和量子干扰效应.
主要成果:
- 获得了D直线过渡的Δν/ν=5×10^{-11}的相对不确定性.
- 与之前的工作相比,不确定性减少了10 (D1) 和30 (D2) 的因素.
- 提取了 ^{2}P 细结构分割 (Δνfs) 的 197,064.54(7) MHz.
- 确定 ^{2}P_{1/2} 超精度常数 (A P1/2) 是 -117.92(4) MHz.
结论:
- 这项研究证明了迄今为止被困离子实验中E1过渡的最高精度.
- 提高精度为测试基本物理和改进原子钟开辟了新的途径.
- 提取的原子参数为原子结构理论提供了关键数据.
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