基于组合拉曼脉冲实现大面积低相噪冷原子干涉仪的实验研究

Cold atom interferometer has been successfully applied in many scientific and technical fields, such as measurements of physical constants and inertial instruments, and it is important to improve the precision of the cold atom interferometer. This project will focus on experimental investigations on large-area low-phase-noise cold atom interferometers based on composite Raman pulses. Firstly, we will design a new scheme of composite Raman pulses by analyzing the sensitivity function, based on an idea composed of the large momentum transfer with the wave vector inversion of Raman pulses and the positive/negative phase-noise suppression. Then, the large-momentum-transfer atom beam splitter and mirror with 8 momentum recoils will be experimentally demonstrated using the composite Raman pulses, and the large-area cold atom interferometer with the low phase noise will be experimentally realized. At the same time, the visibility of the cold atom interference fringe and its phase noise will be experimentally investigated when considering the temperature of cold atoms, the duration of Raman pulses, the wave vector and wave front of Raman lasers. Finally, the phase noise can be well suppressed by carefully adjusting the parameters of composite Raman pulses, and the high-precision cold atom interferometer can be realized with the large area and low phase noise. By the investigation of this project, the supper-precision cold atom interferometer and its applications in precision measurements will be developed in the future.

冷原子干涉仪在基础物理研究和惯性测量方面都有着广泛的应用前景，提高冷原子干涉仪的测量精度有着重要的意义。本项目拟开展基于组合拉曼脉冲实现大面积低相噪冷原子干涉仪的实验研究：首先，基于波矢反转实现大动量转移和正负抵消低频相位噪声的想法，结合灵敏度函数理论分析，设计一种既可增大原子干涉环路面积又可抑制相位噪声的组合拉曼脉冲方案；然后，基于该研究方案，完成8倍光子反冲动量的原子分束和反射镜，实验演示大面积低相噪的冷原子干涉仪，同时，实验研究原子温度、拉曼脉冲持续时间、拉曼光波矢和波前等物理参数对原子干涉条纹对比度及其相位噪声的影响；最后，通过优化组合拉曼脉冲的实验参数来降低相位噪声，实现高精度的冷原子干涉仪。通过本项目的实施，将为进一步开展超高精度冷原子干涉仪及其在精密测量方面的应用奠定基础。

冷原子干涉仪在基础物理研究和惯性测量方面都有广泛的应用前景，提高冷原子干涉仪的测量精度有着重要的意义。本项目开展了基于组合拉曼脉冲实现大面积低相噪冷原子干涉仪的实验研究：首先，基于波矢反转实现大动量转移和正负抵消低频相位噪声的想法，结合灵敏度函数理论分析，设计一种既可增大原子干涉环路面积又可抑制相位噪声的组合拉曼脉冲方案；然后，基于该研究方案，实验演示大面积低相噪的冷原子干涉仪，同时，实验研究原子温度、拉曼脉冲持续时间、拉曼光波矢和波前等物理参数对原子干涉条纹对比度及其相位噪声的影响；最后，构建了原子干涉环路面积达到了1.2 cm^2，灵敏度达到了1.5*10^(-7) rad/s/Hz^0.5，分辨率为9.5*10^(-10) rad/s@20000 s。