报告时间：2026年1月21日  上午9:30 

报告地点：物质科研楼C404会议室   Room C404 Material Science Building

报告人： 张振东教授  香港大学

报告题目/Title: Towards scalable all-optical trapping of an ion array in a multimode confocal cavity

摘要/Abstract:

Ions in radio-frequency (RF) traps have been the driving force for the development of well controlled quantum systems for the exploration of fundamental physics, quantum information processing and precision measurements. Trapped ions are usually limited to the linear chain configuration in the RF trap and scaling up the system size while keeping operation fidelities remain challenging. Trapping ions purely by tightly focused laser beams has emerged as a new research direction during the last decade. The optical microtraps allow flexible spatial arrangement of ions and eliminate the RF-induced micromotion of ions. In this talk, I’ll introduce my group’s effort at HKU towards trapping ions in micron-size synthetic modes formed by the superposition of degenerate transverse modes in an optical confocal cavity. The multimode cavity which supports power-enhanced movable optical tweezers will enable both the tight confinement, spatial rearrangement and Purcell-enhanced microscopy of ions. New quantum logic scheme with ions in an array of microtraps can be implemented without the need to cool ions into their motional ground states.

报告人简介/Curriculum Vitae:

Prof. Zhendong Zhang was born in Wuhan and obtained a B.S. in physics from Huazhong University of Science and Technology. Later he went to US and did his PhD with Prof. Cheng Chin at University of Chicago, where he finished a PhD thesis titled “Coherent dynamics and reactions in atomic and molecular Bose-Einstein condensates” which won the Outstanding Dissertation Award from International Organization of Chinese Physicists and Astronomers (OCPA). He then joined Stanford University as a Bloch Postdoctoral Fellow, where he worked with Prof. Benjamin Lev and finished the construction of an experiment of magnetic quantum gas strongly coupled to a high-finesse multimode optical cavity. In 2025, he joined the Department of Physics at HKU.