Application of phase, amplitude, and polarization shaped pulses for optimal control on molecules

We present a new level of control in closed loop experiments by implementing a shaper setup which is capable of manipulating the phase, amplitude, and polarization of femtosecond laser pulses simultaneously and independently. As a test of this method it is applied to second harmonic generation. The advantage of manipulating all three parameters of the electrical field is demonstrated in the optimization of the multi-photon ionization of NaK in a molecular beam. The obtained pulse shape enhances the ionization yield greatly in comparison to traditional optimizations where only the scalar parameters phase and amplitude have been employed. Moreover, the recorded optimized pulse form reveals the particular optimization path via the selected excited states. (c) 2007 Elsevier B.V. All rights reserved.