Extensions to quantum optimal control algorithms and applications to special problems in state selective molecular dynamics

We present an implementation of an additional cost in the functional of the recently published iteration methods for quantum optimal control [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998)] to design optimal laser pulses for population transfer. The additional criterion takes into account the asymptotic switch on and off behavior of experimentally generated laser pulses. Exemplarily, a specially adapted windowed Fourier transform is applied to decompose a complex, highly nonintuitive optimal laser field in a sequence of subpulses to provide laser pulse parameters as helpful information for experimental reconstruction. Numerical calculations for three typical spectroscopic excitation mechanisms show that laser fields obtained with the new functional signify a step towards experimental feasibility. (C) 1999 American Institute of Physics. [S0021-9606(99)02104-2].