Chapter 16: Design of Femtosecond Pulse Sequences to Control Reactions

Since the invention of the laser in I960, the chemist's dream has been to take advantage of the unique properties of laser light - enormous intensities, precise frequency tunability and perhaps most, importantly, phase coherence - to carry out photochemical reactions selectively and efficiently. Two approaches for achieving this control are described here:
Optimal Control Theory and Multiple Pathway Interference.
The Actual Scheme
FIG. 1: Schematic energy-level diagram of the The Actual Formula two-photon absorption in The Actual Formula Note that there is a continuum of pairs of frequencies under the pulse envelope such that The Actual Formula the two photon resonance frequency. The existence of multiple paths to the same final state gives rise to quantum interference and the possibility of coherent control. The power spectrum of the pulse is shown at the left.