报告题目：CP symmetry test via atomic EDM measurement（通过原子EDM测量检验CP对称性破缺）

报 告 人：Tian Xia(夏添) （University of Science and Technology of China）

报告时间：2023年11月4日（星期六）午9:00-10:00

报告地点：激光光谱研究所三层报告厅

报告简介：

The permanent electric dipole moment (EDM) of atoms, molecules, and elementary particles is predicted in the standard model. While it is too small compared with the experimental measurement sensitivity, it is an important method to search for beyond-standard-model physics via CP violating mechanisms. In this talk, I will focus on the EDM measurement of the 171Yb atoms with atoms held in an optical dipole trap. A quantum nondemolition measurement with a spin-detection efficiency of 50% is realized. A systematic effect due to parity mixing induced by a static E field is observed, and is suppressed by averaging between measurements with optical dipole traps in opposite directions. The coherent spin precession time is found to be much longer than 300 s. The measurement result leads to an upper limit of |d(171Yb)| < 1.5 × 10−26 e cm (95% C.L.). These measurement techniques can be adapted to search for the EDM of 225Ra.

报告人简介：

Tian Xia is a Research Associate Professor of Hefei National Research Center for Physical Sciences at the Microscale at the University of Science and Technology of China. He got his bachelor’s degree at Tsinghua University and Ph.D. at Princeton University. He later worked as a post-doctoral research associate at the University of Wisconsin-Madison on quantum computing with neutral atoms trapped in a 2-D tweezer array. In 2015, he joined USTC. His current focus is the precision measurements with cold atoms and searching for new physics beyond the standard model.