Control of classical regime molecular objectives—Applications of tracking and variations on the theme

Abstract

We examine the applicability of variations of exact tracking, including asymptotic tracking, state-dependent trajectory tracking, and competitive tracking, for the problem of generating feasible external laser fields for control of classically modeled molecular motion via external laser fields. Applications are considered to the selective unimolecular dissociation of the stronger bond of highly coupled linear triatomic molecules. Specifically, we explore two variations of exact tracking, namely, asymptotic energy tracking and competitive acceleration tracking. It is found that, in the former case, a high degree of physical intuition is needed to specify a desirable energy track a priori. In the latter case, less physical intuition is necessary since we only need to specify the desired accelerations for given displacements, momenta and potential at each time instead of following a prescribed track. However, a trade-off with this method arises due to the difficulty in predicting the relevant observables such as the dissociation probability before actually integrating the equations of motions.