报告题目：Coherent Quantum Speed Limits

报  告 人：邱型泽 （同济大学）

报告时间：2024年4月30日（星期二）上午10：00 - 11：00

报告地点：激光光谱研究所三层报告厅

报告简介：

      Quantum speed limits (QSLs) are a topic of broad interest in physics for their fundamental importance, as they provide an operational interpretation to time-energy uncertainty relations. They have also become useful tools in several fields of theoretical and applied quantum physics. In this talk, I will present two infinite families of coherent QSLs for general unitary dynamics by employing the Holder’s inequality for matrix norms. Our approach clearly highlights the contribution of the coherence of the evolved states, and provides novel QSLs characterized by coherence measures based on Schatten p-norm or Hellinger distance. I will illustrate our findings with the Landau-Zener model and a related two-qubit model, demonstrating our bounds can be tighter than the established results and asymptotically saturable in the adiabatic limit. Furthermore, with the techniques of shortcuts to adiabaticity, our bounds can also be saturated at finite time. Our results reveal that fast quantum dynamics demands coherent superpositions of energy eigenstates, singling out coherence as a key resource for unitary evolution.

报告人简介：

      Xingze Qiu got his Ph.D. degree from the University of Science and Technology of China, and then worked at Fudan University as a postdoc. In March 2023, he joined Tongji University as an associate professor. His research interest lies in quantum physics, including quantum simulation, quantum metrology, quantum information, and the interplay between them.