Wave packet interferometry for short-time electronic energy transfer: Multidimensional optical spectroscopy in the time domain

We develop a wave packet interferometry description of multidimensional ultrafast electronic spectroscopy for energy-transfer systems. After deriving a general perturbation-theory-based expression for the interference signal quadrilinear in the electric field amplitude of four phase-locked pulses, we analyze its form in terms of the underlying energy-transfer wave packet dynamics in a simplified oriented model complex. We show that a combination of optical-phase cycling and polarization techniques will enable the experimental isolation of complex-valued overlaps between a ‘‘target’’ vibrational wave packet of first order in the energy-transfer coupling J, characterizing the one-pass probability amplitude for electronic energy transfer, and a collection of variable ‘‘reference’’ wave packets prepared independently of the energy-transfer process. With the help of quasiclassical phase-space arguments and analytic expressions for local signal variations, the location and form of peaks in the two-dimensional interferogram are interpreted in terms of the wave packet surface-crossing dynamics accompanying and giving rise to electronic energy transfer. © 2003 American Institute of Physics. @DOI: 10.1063/1.1519259#