Desorption Dynamics of Rb₂ Molecules off the Surface of Helium Nanodroplets

الأصل · EN

The desorption dynamics of rubidium dimers (Rb₂) off the surface of helium nanodroplets induced by laser excitation is studied employing both nanosecond and femtosecond ion imaging spectroscopy. Similarly to alkali metal atoms, we find that the Rb₂ desorption process resembles the dissociation of a diatomic molecule. However, both angular and energy distributions of detected Rb₂+ ions appear to be most crucially determined by the Rb₂ intramolecular degrees of freedom rather than by those of the Rb₂Heₙ complex. The pump-probe dynamics of Rb₂+ is found to be slower than that of Rb+ pointing at a weaker effective guest-host repulsion for excited molecules than for single atoms.