Two-photon photoselection: an irreducible tensor analysis
A detailed symmetry analysis of two-photon photoselection is presented. The adoption of irreducible tensor methods facilitates the characterization of two-photon excited states probed either by fluorescence or by the absorption of a third photon from a probe laser beam. The theory also enables information on any intervening rotational motion to be derived from suitable polarization studies. A new generalized scheme for the symmetry classification of multiphoton transitions is applied to the photoselection process.