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Third-party-funded project

"Femtosecond Time-Resolved Coherent Four-Wave Mixing Techniques for the State Selective Investigation of Molecular Dynamics of Simple Systems" within the Center Grant (DFG Schwerpunktprogramm) "Femtosecond Spectroscopy of Fundamental Excitations in Atoms, Molecules and Clusters".

Project management at the University of Würzburg:

Participating scientists:

Molecular Dynamics need to be monitored state-selectively. It should be also possible to apply the measurement technique for molecules where little is known about the potentials etc. which is the case for many complex polyatomic molecules. In the experiments molecules were excited with light pulses of less than 100 fs duration. The wave packets prepared by a coherent superposition of vibrational and rotational states move along the potential surfaces. The dynamics of these wave packets gives information about the electronic potentials involved as well as the vibrational and rotational coherences. For the first time the observation of totally separated wave packet motion in the electronically excited and ground states of molecules could be attained by means of femtosecond time-resolved nonlinear four-wave mixing spectroscopy. Selectivity can be achieved by changing the laser parameter (wavelength, polarisation), by varying the relative time delay between the different laser pulses and by changing the detection wavelength. Spectral selectivity for the investigation of the dynamics is possible by the application of broadband detection of the nonlinear signals. Especially for more complex molecular or solid-state systems a much more detailed investigation of the dynamics of the different modes can be achieved.

Key words:
    Femtosecond Spectroscopy
    Four-wave mixing spectroscopy

Projekt period: from 01.1999 to 12.2001

Funding institution:
DFG ( Schwerpunktprogramm, dritte Förderperiode )

Preceding project:
Schwerpunktprogramm, zweite Förderperiode