Achieving high-fidelity control of quantum systems is of fundamental
importance in physics, chemistry and quantum information sciences. However, the
successful implementation of a high-fidelity quantum control scheme also
requires robustness against control field fluctuations. Here, we demonstrate a
robust optimization method for control of quantum systems by optimizing the
spectral phase of an ultrafast laser pulse, which is accomplished in the
framework of frequency domain quantum optimal control theory. By incorporating
a filtering function of frequency into the optimization algorithm, our
numerical simulations in an abstract two-level quantum system as well as in a
three-level atomic rubidium show that the optimization procedure can be
enforced to search optimal solutions while achieving remarkable robustness
against the control field fluctuations, providing an efficient approach to
optimize the spectral phase of the ultrafast laser pulse to achieve a desired
final quantum state of the system.Comment: 17 pages, 8 figure