Beyond the Bloch equations: A wave function-based approach to selective excitation in condensed media

An optimization procedure for producing selective excitation of molecules undergoing stochastic dephasing collisions is presented. The collisional effects are incorporated by propagating the Schrödinger equation with random perturbations. The optimization procedure utilizes gradients of the perturbation-averaged physical objective with respect to the laser field parameters; we demonstrate on a model problem that very few averages over collisional events suffice to yield converged results. Therefore, this method is computationally efficient because large averaging of dynamical simulations is not necessary. These results show the viability of the optimal control procedure for application to controlling chemical reactions in solution.