STU-GTIIT光学论坛（No. 40）
报告地点：at lecture hall E503 in the North Campus of GTIIT
报告时间：2025年3月17日 17:00
报告题目: Study on the nonequivalence between geometric-phase definitions and coherent control of electron dynamics with bicircular fields(全英)
报告人：Xiaosong Zhu (Huazhong University of Science and Technology, Wuhan 430074, China)
报告摘要:
The states dressed in tailored two-color laser fields, particularly the bicircular fields, provide an unprecedented platform for studying some fundamental physical questions. I will mainly introduce our theoretical studies to clarify the nonequivalence between geometric-phase definitions [1]. We proved, utilizing the saddle-point method, that the Aharonov-Anandan (AA) phase [2], which was commonly believed to be the non-adiabatic generalization of Berry phase, does not necessarily converge to the Berry phase [3] in the adiabatic limit. This happens as the degeneracy leads to a slow convergence of the quantum states to adiabaticity. The nonequivalence is also numerically demonstrated based on the Floquet theory. Moreover, we show the bicircular field, steering the system through a degeneracy, can cause a π shift of the Berry phase. I may also briefly introduce some of our recent works on coherent control of electron dynamics in other systems with the bicircular fields.
1. Zhu, X., Lu, P., & Lein, M. Control of the geometric phase and nonequivalence between geometric-phase definitions in the adiabatic limit. Phys. Rev. Lett. 128, 030401, 2022.
2. Anandan, J., & Aharonov, Y. Phase change during a cyclic quantum evolution. Phys. Rev. Lett. 58, 1593, 1987.
3. Berry, M. V. Quantal phase factors accompanying adiabatic changes. Proc. R. Soc. A 392, 45, 1984.
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理学院
2025年3月13日
