000196115 001__ 196115
000196115 005__ 20181203023417.0
000196115 0247_ $$2doi$$a10.1063/1.4843235
000196115 022__ $$a0021-9606
000196115 02470 $$2ISI$$a000328729000002
000196115 037__ $$aARTICLE
000196115 245__ $$aCommunication: Angular momentum alignment and fluorescence polarization of alkali atoms photodetached from helium nanodroplets
000196115 260__ $$bAmer Inst Physics$$c2013$$aMelville
000196115 269__ $$a2013
000196115 300__ $$a4
000196115 336__ $$aJournal Articles
000196115 520__ $$aThe theory of photofragments angular momentum polarization is applied to the photodetachment of an electronically excited alkali atom from a helium nanocluster (N = 200). The alignment of the electronic angular momentum of the bare excited alkali atoms produced is calculated quantum mechanically by solving the excited states coupled equations with potentials determined by density functional theory (DFT). Pronounced oscillations as a function of excitation energy are predicted for the case of Na@(He)(200), in marked contrast with the absorption cross-section and angular distribution of the ejected atoms which are smooth functions of the energy. These oscillations are due to quantum interference between different coherently excited photodetachment pathways. Experimentally, these oscillations should be reflected in the fluorescence polarization and polarization-resolved photoelectron yield of the ejected atoms, which are proportional to the electronic angular momentum alignment. In addition, this result is much more general than the test case of NaHe200 studied here. It should be observable for larger droplets, for higher excited electronic states, and for other alkali as well as for alkali-earth atoms. Detection of these oscillations would show that the widely used pseudo-diatomic model can be valid beyond the prediction of absorption spectra and could help in interpreting parts of the dynamics, as already hinted by some experimental results on angular anisotropy of bare alkali fragments. (C) 2013 AIP Publishing LLC.
000196115 700__ $$aHernando, Alberto
000196115 700__ $$aBeswick, J. Alberto
000196115 700__ $$aHalberstadt, Nadine
000196115 773__ $$j139$$tJournal Of Chemical Physics$$k22
000196115 909C0 $$xU10095$$0252439$$pISIC
000196115 909CO $$pSB$$particle$$ooai:infoscience.tind.io:196115
000196115 937__ $$aEPFL-ARTICLE-196115
000196115 973__ $$rREVIEWED$$sPUBLISHED$$aEPFL
000196115 980__ $$aARTICLE