【时   间】16-Aug-2023（Wednesday）2:30PM (Beijing time)

【地   点】Room 526

【报告人】Dayou Yang（Ulm University, Germany）

【主持人】Li You（Tsinghua University & BAQIS）

【题   目】New opportunities for sensing via continuous measurement

【摘  要】

The continuous monitoring of driven-dissipative quantum optical systems provides key strategies for the implementation of quantum metrology, with prominent examples ranging from the gravitational wave detectors to the emergent driven-dissipative many-body sensors. Fundamental theoretical questions about the ultimate performance of such a class of sensors remain open—for example, can they achieve quantum-enhanced precision scaling without squeezed input; how to perform the optimal measurement to approach their ultimate precision? In this talk, I will present our recent efforts [1,2] to answer these questions. In the first part I will introduce dissipative criticality as a resource for nonclassical precision scaling for continuously monitored sensors, by establishing universal scaling laws of the quantum Fisher information in terms of the critical exponents of generic dissipative critical points. In the second part I will present a general continuous measurement strategy to retrieve the full quantum Fisher information of the nonclassical, temporally correlated fields emitted by generic open quantum sensors, thereby to achieve their fundamental precision limit. 

[1] T. Ilias, D. Yang, S. F. Huelga and M. B. Plenio, Criticality-enhanced quantum sensing via continuous measurement, PRX QUANTUM 3, 010354 (2022).

[2] D. Yang, S. F. Huelga and M. B. Plenio, Efficient information retrieval for sensing via continuous measurement, PRX 13, 031012 (2023).

【报告人简介】Dayou Yang earned his BS and MS from Tsinghua Univ. under the advisement of Prof. Li You, and PhD from University of Innsbruck/Austrian academy of science under the supervision of Prof. Peter Zoller. He is now a postdoc researcher in the group of Martin Plenio at Ulm University. His research interests include (1) theoretical quantum optics, in particular the theory of quantum noise, quantum measurement and control; (2) quantum sensing, simulation and information processing with trapped ions, cavity QED, NV centers in diamond and Rydberg atoms; (3) open quantum systems and non-equilibrium dynamics, including non-Markovian dynamics, quantum thermalization and Floquet dissipative systems.