OPTIMAL-CONTROL OF MULTISURFACE MOLECULAR-SYSTEMS

We report a theoretical framework for the study of the optimal control of multisurface molecular systems via a set of nondegenerate excitati on fields. The resulting control equations in the strong response regi me are presented in terms of both the Liouville-space density matrix d ynamics and the Hilbert-space wave function evolution. We further deri ve a pair of eigenequations for the optimal pump-pump fields in the pu re-state control of three-surface molecular systems in the weak respon se regime. The globally optimal pair of pump-pump fields in this case are identified. Application to the control of a rovibronic level on th e final excited surface reveals a symmetry relation within the optimal pair of pump-pump fields in the weak response regime. For numerical d emonstrations, we consider the control of the I-2 molecular system inv olving the initial ground X, the intermediate B, and the final E surfa ce. The target is chosen as an outgoing vibrational wave packet in the hound region of the final E electronic state. The optimal control fie lds in both the strong and weak response regimes are calculated and fu rther parameterized to fit simple experimentally realizable laser puls es. (C) 1998 American Institute of Physics.