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arXiv · 1507.01381

Phase-modulated electronic wave-packet interferometry reveals high resolution vibronic spectra of free Rb atoms and Rb*He molecules

Lukas Bruder·Marcel Mudrich·Frank Stienkemeier
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Abstract

Phase-modulated wave-packet interferometry is combined with mass-resolved photoion detection to investigate rubidium atoms attached to helium nanodroplets in a molecular beam experiment. The spectra of atomic Rb electronic states show a vastly enhanced sensitivity and spectral resolution when compared to conventional pump-probe wave-packet interferometry. Furthermore, the formation of Rb*He exciplex molecules is probed and for the first time a fully resolved vibrational spectrum for transitions between the lowest excited $5\Pi_{3/2}$ and the high-lying electronic states $2^2\Pi$, $4^2\Delta$, $6^2\Sigma$ is obtained and compared to theory. The feasibility of applying coherent multidimensional spectroscopy to dilute cold gas phase samples is demonstrated in these experiments.

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Lukas Bruder, Marcel Mudrich, Frank Stienkemeier. 2015-07-06. Phase-modulated electronic wave-packet interferometry reveals high resolution vibronic spectra of free Rb atoms and Rb*He molecules. https://doi.org/10.1039/c5cp03868e

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