Optimal laser control of molecular orientation: some numerical results

We present some numerical results related to the laser control of molecular orientation. The goal is to orient a linear molecule in the direction of the linearly-polarized laser field. We either want to have the molecule oriented with the field to a high degree at (at least) one time during the time interval considered or we want this orientation to be kept as long as possible, even if it is not as good. The control parameters are the laser field parameters: frequencies, relative phases, maximum field amplitudes and the times determining the envelope shapes. We use different objective functions measuring the orientation which are computed by solving the time-dependent Schrodinger equation including the interaction term between the laser field and the molecular system. We only consider the case of a rigid rotor, i.e., where the wave function depends only on one space variable (angle). In order to optimize the laser field we use two different classes of algorithms: gradient-like algorithms and evolutionary algorithms (EAs). Some promising results have been obtained and are presented here.