Title :

Optimal Control of Quantum Systems

Speaker :

Dr. Haidong Yuan

Postdoctoral Fellow

Massachusetts Institute of Technology, USA

Venue :

Room 215, William M. W. Mong Engineering Building, CUHK

Date :

May 5, 2010, Wednesday
2:30 PM - 3:30 PM

Abstract :

Modern scientific inquiry and the demands of advancing technology are driving theoretical and experimental research towards control of quantum systems. Compelling applications for quantum control have been noted and have motivated seminal studies in such wide-ranging fields as quantum computation, metrology, chemistry, spectroscopy, optical networking and computer science. In most of these applications, the system of interest is rarely isolated but interacts with its environment. This in practice results in signal loss and limits the range of applications. It is therefore of utmost importance to control these systems in a time optimal manner before decoherence corrupts the system of interest.

In this talk I will focus on the time optimal control of spin systems in quantum computing and spectroscopy where radio frequency pulses are used in to implement a unitary transfer of state. The pulse sequences that accomplish a desired transfer should be as short as possible in order to minimize the effects of relaxation and to optimize the sensitivity of the experiments. I will give an analytical characterization of such time optimal pulse sequences applicable to coherence transfer experiments in multiple-spin systems. I also give a complete characterization of the reachable set for a class of bilinear control systems which arise from these concrete physical systems.

Biography :

Dr. Haidong Yuan received his B.E. in Electrical Engineering from Tsinghua University, China, M.S. in Engineering Science and Ph.D. in Applied Mathematics both from Harvard University, US. He is now at Massachusetts Institute of Technology as a post-doctoral fellow.

    **************************************** ALL ARE WELCOME ****************************************

Enquiries: Ms. Winnie Wong or Prof. Wen J. Li, Department of Mechanical and Automation Engineering, CUHK at 2609 8337. *MAE Series (2009-10) is contained in the World-Wide Web home page at http://www3.mae.cuhk.edu.hk/maeseminars.php#mae.