Sub-optical-cycle coherent control in nonlinear optics

The sub-optical coherent control in nonlinear optics was discussed. The intra-atomic phase matching that highlights fundamental differences between high harmonic generation (HHG) and other nonlinear processes was demonstrated. A pulse shaping apparatus in conjunction with survival of the fittest algorithm was used to find the optimum pulse shape. It was shown that the intensity of the 27th harmonic can be increased by 1 order of magnitude over that which was obtained with a transform-limited pulse.