Electronic coherence in pseudo two-colour pump-probe spectroscopy

We have investigated the appearance of coherence in pseudo two-colour pump-probe spectroscopy, and have numerically analyzed the usefulness of this method for extracting information on electronic coherence dynamics. A number of distinct characteristics are found that would allow a determination of dephasing times from the data, both when the dephasing dynamics occurs on a longer and shorter time-scale than set by the time-resolution resulting from the used laser pulses. A severe limitation is, however, that all these characteristic traits vanish once inhomogeneity governs the absorption line shape. Nevertheless, the method seems very suitable for unravelling spectra and dynamics in case of several overlapping homogeneous bands.