Sampling-based robust control in synchronizing collision with shaped laser pulses: An application in charge transfer for H⁺ + D → H + D⁺

In laser-assisted collisions, a control field may fail if we cannot precisely synchronize the colliding particles and the laser pulse. In this paper, we show that laser pulses that are robust in this situation can be obtained by a sampling-based method to achieve a desired charge transfer probability with limited sensitivity to the arrival time of the laser pulses. The time-dependent wave packet method and an adaptive target scheme are used in optimal control calculations based on an adiabatic two-state model of a H + D⁺ collision system. Several samples with different pulse arrival times are selected to construct robust fields at two different collision energies and the validity of these fields are examined by tests with additional samples. Excellent performance was obtained with the robust fields in both cases.