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arXiv · 1309.6662

High resolution photoassociation spectroscopy of the $^{6}$Li$_2$ $1^{3}Σ_{g}^{+}$ state

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

We present experimental observations of seven vibrational levels $v'=20-26$ of the $1^{3}Σ_{g}^{+}$ 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, for the first time, determine the spin-spin and spin-rotation interaction constants for this state. The absolute uncertainty of our measurements is $\pm 0.00002$ cm$^{-1}$ ($\pm 600$ kHz). We use these new data to further refine an analytic potential for this state.

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Mariusz Semczuk, Xuan Li, Will Gunton, Magnus Haw, Nikesh S. Dattani, Julien Witz, Arthur Mills, David J. Jones, Kirk W. Madison. 2013-09-25. High resolution photoassociation spectroscopy of the $^{6}$Li$_2$ $1^{3}Σ_{g}^{+}$ state. https://doi.org/10.1103/physreva.87.052505

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