邀请人 (Invited by): 柳奎

时间 (Time):星期一，2023/6/5-14:30-16:00

地点 (Location): 珠海校区天琴中心3217会议室

摘要 (Abstract): 

Trapped-ion quantum sensors have become highly sensitive tools for the search of physics beyond the Standard Model. In this talk, I will focus on the recent measurements on the test of local Lorentz -invariance (LLI) with a single Yb+ ion and isotope shift measurements for the search of the fifth force mediated by a potential dark matter boson.

With high-precision spectroscopy of non-spherical electron orbital states in a Michelson-Morley type experiment, we search for the violation of LLI. We constrained the symmetry breaking coefficients at the 10-21 level and these results represent the most stringent test of this type of violation in the combined electron-photon sector.

Theoretical proposals suggest a dark matter boson mediating the fifth force and would couple the neutrons and electrons in an atom. This coupling would lead to a small shift in energy levels. To distinguish this shift from the less accurately calculated nuclear effects, isotope shifts and King plot analysis have been used. With improved accuracy by factors of 10 to 100 for the measured isotope shifts compared to currently published values, we hope to shine some light into the observed nonlinearity of the King plot in ytterbium.

主讲人简介 (Speaker's CV): 

叶志涵，德国联邦物理技术研究院（PTB）与汉诺威大学联合培养在读博士研究生。2016年本科毕业于武汉大学物理科学与技术学院物理学天眷班，2019年于德国汉诺威大学获得硕士学位，之后在德国联邦物理技术研究院与汉诺威大学攻读博士至今。主要研究方向为基于离子囚禁光谱的洛伦兹不变性实验检验与暗物质探寻，目前已利用囚禁的镱离子系统将洛伦兹对称性破缺系数约束在10^(-21)级，这是迄今为止在电子-光子联合中给出洛伦兹破缺的最强限制。实验上将镱离子同位素频移测量精度提高了1～2个数量级，为基于离子囚禁光谱的暗物质玻色子探寻打下了坚实的基础。