OPTICAL CONTROL OF MOLECULAR-MOTION WITH ROBUSTNESS AND APPLICATION TO VINYLIDENE FLUORIDE

The results of previous research [J. Chem. Phys. 88, 6870 (1988)] on optimal control of harmonic molecular motion are extended. A closed-form solution for the optimal optical field is derived for a quadratic cost criterion, and an asymptotic form for this field is obtained for large target times. The dynamics of a molecule are shown to be controllable if no normal mode has zero optical absorption intensity. The theoretical formulation yields optical field designs that are to be executed ultimately in the laboratory. In this regard, a critical issue is the robustness of the field designs. Therefore the optimal control formalism is extended further to yield optimal fields that exhibit minimal sensitivity of the desired molecular objectives with respect to force constants and dipole derivatives. Examples of sensitivity minimization are shown, using a linear chain molecule. Finally, optimal control of the molecule vinylidene fluoride is demonstrated. © 1990 Optical Society of America.