基于光纤光梳的高分辨率直接光谱研究

项目名称： 基于光纤光梳的高分辨率直接光谱研究

项目编号： No.61405002

项目类型： 青年科学基金项目

立项/批准年度： 2015

项目学科： 信息四处

项目作者： 夏巍

作者单位： 北京大学

项目金额： 9万元

中文摘要： 本项目围绕精密计量学科中精密光谱测量的科学问题，探索高精度直接光谱学的测量新方法。从激光源和测量原理进行测量技术的创新，在碱金属原子精密光谱测量的方案研究和技术方面有所突破，将连续激光引入飞秒光梳与热原子气体的相互作用，构建了碱金属原子的双光子吸收理论模型，提出了铷原子及铯原子的双光子跃迁直接光谱学技术，通过扫描光梳重复频率，可以获取光梳覆盖范围内原子的所有双光子跃迁谱线，并实现双光子跃迁光学频率的测量，测量不确定度达到千赫兹水平。此外，可通过调节连续激光的频率对跃迁路径及原子速度可控的双光子跃迁现象进行研究。这些研究成果将构成新的系统的精密光谱学测量理论与技术，对精密测量物理研究具有重要的科学意义和研究价值。

中文关键词： 光纤光学频率梳；双光子跃迁；直接光谱学；偏振光谱；精密测量

英文摘要： For the scientific research of precise spectroscopy measurement in the precision metrology, this project explores some new methods for direct spectroscopy based on optical frequency combs. The proposed approach for investigating the transitions in alkali atoms, iodine molecules and Bose-Einstein Condensate (BEC) carries on innovation of the laser source and optical configurations. A continuous wavelength laser is introduced to the interaction between a frequency comb and the atoms and the corresponding theoretical model has been established. The two-photon direct spectroscopy technology of the Rb and Cs has been proposed and the absolute frequency of the transition can be measured at a kilo hertz level. Based on the combination of multiple heterodyne method and the enhancing cavity technique, high resolution iodine molecule direct spectroscopy technology has been demonstrated for fast abundant transition lines precision measurement. Besides, by using modulation-transfer spectroscopy technology, the precision measurement of the stimulated shift of the BEC has been developed in order to verify the theoretical predictions. Therefore, those research results will lead to new theories and technologies of precision spectroscopy based on the optical frequency comb, which has profound scientific significance and research

英文关键词： fiber-based optical frequency comb；two-photon transition；direct frequency comb spectroscopy；polarization spectroscopy；precision measurement