M.F Emde

SPECTRAL INTERFEROMETRY AS AN ALTERNATIVE TO TIME-DOMAIN HETERODYNING

A novel method of time resolving the amplitude and phase of a transient nonlinear-optical polarization, based on Fourier transformation of a spectral interference pattern, is discussed. We show that with this technique the delay at which the polarization is generated can be retrieved. The method is demonstrated in a transient four-wave-mixing experiment on a dye solution.

Hydrated electron dynamics on a 5-fs timescale

We report on frequency-resolved pump-probe and photon echo experiments on the equilibrated aqueous electron using 5-fs pulses. All experiments exhibit a signature of wave packet dynamics attributed to librational motions of water molecules.

Photon-echo spectroscopy of the hydrated electron with 5-fs pulses

Employing photon-echo techniques with extremely short laser pulses that consist of only few optical cycles, we investigate the dynamics of the equilibrated hydrated electron. The pure dephasing time of the hydrated electron deduced from the measurements is -1.6 fs. The shape of the absorption spectrum is described excellently by an extended Lorentzian contour the spectral width of which is fully determined by the pure dephasing time.

Phase-Locked Femtosecond Photon Echo: A New Dimension in Ultrafast Spectroscopy

Phase-locked femtosecond heterodyne-detected stimulated photon echo is shown to provide a new dimension to the exploration of solute-solvent interaction. As an example, we present and discuss results of phase-locked hole burning experiments on a dye solution at room temperature. The potential of this technique for the exploration of optical dynamics in photobiological systems is emphasized.