用于辐射温度计的原子和分子系统
Stephen Eckel1, Christopher Holloway2, Eric Norrgard1
1Sensor Sciences Division, National Institute of Standards and Technology Physical Measurement Laboratory, Gaithersburg, MD, USA.
概括
研究人员开发了新的原子传感器,用于辐射温度测量. 这些设备利用激光冷却的原子精确测量黑体辐射,为改善温度标准铺平了道路.
科学领域:
- 量子物理学 量子物理学 是一种量子物理学.
- 计量学 计量学 计量学
- 原子物理 原子物理
背景情况:
- 原子和分子为开发精确的测量标准和传感器提供了独特的特性.
- 量子力学决定了原子的性质,使它们成为基本测量的理想选择.
- 辐射温度测量在科学和工业应用中至关重要.
研究的目的:
- 用原子和分子创建辐射温度标准和传感器的新概念.
- 介绍两个不同的基于原子的温度测量系统的实验结果.
- 详细说明用于解释实验数据的理论框架,包括速率方程模型.
主要方法:
- 使用冷原子温度计 (CAT) 中的激光冷却的85Rb瑞德伯格原子,探测130GHz附近的黑体辐射 (BBR).
- 使用一个紧的BBR原子传感器 (CoBRAS) 与85Rb蒸汽监测与BBR相关的光在24.5 THz附近.
- 应用速率方程模型来解释原子过渡和BBR之间的相互作用.
主要成果:
- 在CAT取得了初级温度测量与大约1%的不确定性,并有可能进一步降低.
- 科布拉斯在测量黑体光谱时表现出极好的u(T) ≈0.13K的相对精度.
- 这两项实验都展示了原子系统的可行性,用于精确的辐射温度确定.
结论:
- 原子和分子可以作为新的标准和辐射温度传感器的基础元素.
- 开发的冷原子温度计和紧的BBR原子传感器代表了初级温度计的重大进步.
- 这些基于原子的方法为重新定义符合量子原理的温度测量提供了有希望的途径.
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