报告题目：基于冷铷原子气体相干布居数囚禁的多脉冲Ramsey干涉实验

报告人：李朝红教授  中山大学

报告时间：2021年11月15日（周一） 10：00

报告地点：理6栋302       邀请人：张善超

报告内容：

        Ramsey spectroscopy via coherent population trapping (CPT) is essential in precision measurements. The conventional CPT-Ramsey fringes contain numbers of almost identical oscillations and so that it is difficult to identify the central fringe. Here we experimentally demonstrate a temporal analog of Fabry–Pérot resonator via double-Λ CPT of laser-cooled 87Rb atoms. By inserting a periodic CPT pulse train between the two CPT-Ramsey pulses, due to the constructive interference of spin coherence, the transmission spectrum appears as a comb of equidistant peaks in frequency domain and thus the central Ramsey fringe can be easily identified. From the five-level Bloch equations for our double-Λ system, we find that the multi-pulse CPT interference can be regarded as a temporal analog of Fabry–Pérot resonator. Because of the small amplitude difference between the two Landé gfactors, each peak splits into two when the external magnetic field is not too weak. This splitting is exactly linear with the magnetic field strength and thus can be used for measuring a magnetic field without involving magneto-sensitive transitions.

专家简介：

        李朝红，中山大学物理与天文学院教授、博导，广东省量子精密测量与传感重点实验室主任。2019年起任中国物理学会第九届原子与分子物理专业委员会委员、中国光学学会光量子科学与技术专业委员会委员，2020年获国家杰出青年科学基金资助、入选科技部中青年科技创新领军人才。主要研究冷原子物理与量子精密测量，代表性成果有: (1)光晶格冷原子体系的量子关联与相变; (2)玻色凝聚原子体系量子相变动力学的普适特性表征; (3)基于多粒子干涉与相变的量子精密测量。已发表SCI论文90余篇，包括9篇Phys. Rev. Lett.[第一/通讯作者6篇(含独著3篇)]和1篇Rev. Mod. Phys. [共同通讯作者]等，5个理论被实验证实/采用。Google学术被引2500余次，9篇论文单篇被引超过100次。