Observation of all-trans-β-carotene wavepacket motion on the electronic ground and excited dark state using degenerate four-wave mixing (DFWM) and pump–DFWM

Wavepacket dynamics on the ground and on the optically dark, first electronic state of all-trans-β-carotene is presented. Ground state dynamics are studied using resonant and non-resonant degenerate four-wave mixing spectroscopy with 16 fs time resolution. Wavepacket motion on the electronic dark state was monitored using pump-degenerate four-wave mixing spectroscopy.