报告摘要:
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, 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. Radio frequency pulses are used in coherent
spectroscopy to implement a unitary transfer of state. 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.

报告人简介:
Haidong Yuan received his B.E. in Electrical Engineering from Tsinghua
University, Beijing in 2001, M.S. in Engineering Science and Ph.D. in
Applied Mathematics from Harvard University in 2002 and 2006
respectively. Since 2006, he is at Massachusetts Institute of Technology
as a post-doctoral fellow.