基于量子逻辑技术的铝离子光频标研究进展

Research progress of Al^+ ion optical frequency standard based on quantum logic technique

光频标(光钟)在时间及长度定义、基本物理常数及其随时间变化的测量、相对论检验、甚长基线干涉仪、测地学以及全球卫星导航定位等领域都有广泛的应用.一台光频标由超稳激光、光梳和囚禁的离子或原子组成.其准确度受到多普勒频移、塞曼频移、斯塔克频移、碰撞频移、黑体辐射频移等的影响.其中黑体辐射频移是对于系统误差影响较难评估也较难控制的一项,而铝离子在目前所有正在发展的光频标里面是黑体辐射频移最小的一个,其不确定度仅有4.0×10^(-19),因此铝离子光频标是很有前途的一种光频标.本文将分别介绍光频标的3个组成部分,以及当前基于量子逻辑技术铝离子频标的基本原理和华中科技大学的最新研究进展.

Optical atomic clocks have many applications in the definition of the time and the length, measurement of fundamental constants and their potential variations with time, testing of relativity, very long baseline interferometry, geodesy, and global navigation satellite systems. An optical clock consists of three parts： ultra-stable laser, frequency comb and trapped ions or atoms. The accuracy of optical atomic clocks can be affected by Doppler shift, Zeeman shift, Stark shift, collision shift, blackbody radiation （BBR） shift, etc. The BBR shift is very difficult to be characterized and controlled. Among all optical atomic clocks under current development, Al^＋ optical clock has the smallest BBR shift at a level of 4.0 × 10^-19, therefore the Al^＋ is a promising ion for high-accuracy optical frequency standard. In this article we give a review on the three parts of optical frequency standards, the basic working principle of Al^＋ ion optical frequency standard based on quantum logic technique, and research progress of an Al^＋ optical clock under development at Huazhong University of Science and Technology.