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arXiv:1309.6662 · Physical Review A

High-resolution photoassociation spectroscopy of the 6 Li 2 13Σg+ state

Mariusz Semczuk, Xuan Li, Will Gunton, Magnus A. Haw, Nikesh S. Dattani, Julien Witz, Arthur K. Mills, David J. Jones, Kirk W. Madison

Published May 9, 2013• 28 citations
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Abstract

We present experimental observations of seven vibrational levels, ${v}^{\ensuremath{'}}=20$--26, of the ${1}^{3}{\ensuremath{\Sigma}}_{g}^{+}$ excited state of Li${}_{2}$ molecules by the photoassociation (PA) of a degenerate Fermi gas of ${}^{6}$Li atoms. For each vibrational level, we resolve the rotational structure using a Feshbach resonance to enhance the PA rates from $p$-wave collisions. We also determine the spin-spin and spin-rotation interaction constants for this state. The absolute uncertainty of our measurements is $\ifmmode\pm\else\textpm\fi{}0.00002$ cm${}^{\ensuremath{-}1}$ ($\ifmmode\pm\else\textpm\fi{}600$ kHz). We use this data to further refine an analytic potential for this state.

DOI
10.1103/physreva.87.052505

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Photoassociation spectroscopy of the B Π1 state of LiCs

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We present an accurate potential energy curve of the B (1)Pi state in the LiCs molecule for which vibrational levels between v(') = 0 and v(') = 35 (bound by 11.4 GHz) were measured by photoassociation spectroscopy in an ultracold ensemble of (7)Li and (133)Cs atoms. By the combination of conventional spectroscopic data of the B-X system and the new photoassociation measurements a very precise value of the dissociation energy of the ground state X (1)Sigma(+) of LiCs was determined to be D(0) = 5783.495(5) cm(-1).

The Journal of Chemical Physics•Aug 4, 2009•23 citations
We present experimental observations of seven vibrational levels, v\ensuremath′=20{v}^{\ensuremath{'}}=20v\ensuremath′=20--26, of the 13\ensuremathΣg+{1}^{3}{\ensuremath{\Sigma}}_{g}^{+}13\ensuremathΣg+​ excited state of Li2{}_{2}2​ molecules by the photoassociation (PA) of a degenerate Fermi gas of 6{}^{6}6Li atoms. For each vibrational level, we resolve the rotational structure using a Feshbach resonance to enhance the PA rates from ppp-wave collisions. We also determine the spin-spin and spin-rotation interaction constants for this state. The absolute uncertainty of our measurements is \ifmmode±\else\textpm\fi0.00002\ifmmode\pm\else\textpm\fi{}0.00002\ifmmode±\else\textpm\fi0.00002 cm\ensuremath−1{}^{\ensuremath{-}1}\ensuremath−1 (\ifmmode±\else\textpm\fi600\ifmmode\pm\else\textpm\fi{}600\ifmmode±\else\textpm\fi600 kHz). We use this data to further refine an analytic potential for this state.
We present spectroscopic measurements of seven vibrational levels v=29−−35v=29--35v=29−−35 of the $A({1}^{1}{\ensuremath{\Sigma}}_{u}^{+})$ excited state of Li2{}_{2}2​ molecules by the photoassociation of a degenerate Fermi gas of 6{}^{6}6Li atoms. The absolute uncertainty of our measurements is $\ifmmode\pm\else\textpm\fi{}0.000\phantom{\rule{0.16em}{0ex}}02$ cm${}^{\ensuremath{-}1}$ ($\ifmmode\pm\else\textpm\fi{}600$ kHz) and we use these new data to further refine an analytic potential for this state. This work provides high accuracy photoassociation resonance locations essential for the eventual high-resolution mapping of the $X({1}^{1}{\ensuremath{\Sigma}}_{g}^{+})$ state enabling further improvements to the sss-wave scattering length determination of Li and enabling the eventual creation of ultracold ground-state 6{}^{6}6Li2{}_{2}2​ molecules.
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High resolution photoassociation spectroscopy of the excited c3Σ1+c^3Σ_{1}^+c3Σ1+​ potential of 23^{23}23Na133^{133}133Cs
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We present an accurate potential energy curve of the B (1)Pi state in the LiCs molecule for which vibrational levels between v(') = 0 and v(') = 35 (bound by 11.4 GHz) were measured by photoassociation spectroscopy in an ultracold ensemble of (7)Li and (133)Cs atoms. By the combination of conventional spectroscopic data of the B-X system and the new photoassociation measurements a very precise value of the dissociation energy of the ground state X (1)Sigma(+) of LiCs was determined to be D(0) = 5783.495(5) cm(-1).