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Alkali Atoms Attached to $^3$He Nanodroplets

R. Mayol·F. Ancilotto·M. Barranco·O. Bünermann·M. Pi·F. Stienkemeier
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Abstract

We have experimentally studied the electronic $3p-> 3s$ excitation of Na atoms attached to $^3$He droplets by means of laser-induced fluorescence as well as beam depletion spectroscopy. From the similarities of the spectra (width/shift of absorption lines) with these of Na on $^4$He droplets, we conclude that sodium atoms reside in a ``dimple'' on the droplet surface and that superfluid-related effects are negligible. The experimental results are supported by Density Functional calculations at zero temperature, which confirm the surface location of Na, K and Rb atoms on $^3$He droplets. In the case of Na, the calculated shift of the excitation spectra for the two isotopes is in good agreement with the experimental data.

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R. Mayol, F. Ancilotto, M. Barranco, O. Bünermann, M. Pi, F. Stienkemeier. 2004-10-27. Alkali Atoms Attached to $^3$He Nanodroplets. https://doi.org/10.1007/s10909-005-1555-1

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