PHYSICAL REVIEW A, cilt.57, sa.4, ss.2420-2425, 1998 (SCI-Expanded)
This work presents a general framework for assessing the quality and robustness of control over quantum dynamics induced by an optical field epsilon(t). The control process is expressed in terms of a cost functional, including the physical objectives, penalties, and constraints. The first variations of such cost functionals have traditionally been utilized to create designs for the controlling electric fields. Here, the second variation of the cost functional is analyzed to explore (i) whether such solutions are locally optimal, and (ii) their degree of robustness. Both issues may be assessed from the eigenvalues of the stability operator S whose kernel K(t, tau) is related to delta epsilon(t)/delta epsilon(tau)\(c) for 0