ECE Seminar - Linear quantum systems and their applications in experimental quantum physics
Abstract: The Kalman canonical form is a standard result in classical linear systems theory. In this talk, we discuss quantum linear systems from a control-theoretic point of view. After that we present the quantum Kalman canonical form. As an application, we show how it can be used to study decoherence-free modes, quantum non-demolition variables, and back-action evading measurements in quantum information science. The proposed theory will be demonstrated by several experiments from quantum optics and opto-mechanical systems, including:
1. Optomechanical dark mode, Dong et al., Science, 338:609--1613, 2012.
2. Quantum backaction evading measurement of collective mechanical modes, Ockeloen-Korppi, et al., Physical Review Letters, 117:140401, 2016.
3. Light-mediated strong coupling between a mechanical oscillator and atomic spins 1 meter apart, Karg, et al., Science 369:174–179, 2020.
4. Quantum mechanics–free subsystem with mechanical oscillators, de Lepinay, et al., Science 372:625–629, 2021.
Prof. Guofeng Zhang received his B.Sc. degree and M.Sc. degree from Northeastern University, Shenyang, China, in 1998 and 2000 respectively. He received a Ph.D. degree in Applied Mathematics from the University of Alberta, Edmonton, Canada, in 2005. During 2005–2006, he was a Postdoc Fellow in the Department of Electrical and Computer Engineering at the University of Windsor, Windsor, Canada. He joined the School of Electronic Engineering of the University of Electronic Science and Technology of China, Chengdu, Sichuan, China, in 2007. From April 2010 to December 2011 he was a Research Fellow in the School of Engineering of The Australian National University. He joined the Hong Kong Polytechnic University in December 2011 and is currently an Associate Professor in the Department of Applied Mathematics. His research interests include quantum information, quantum control, quantum algorithms, and tensor computation.