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arXiv:1104.3674 · Physical Review A

Hyperfine, rotational, and Zeeman structure of the lowest vibrational levels of the Rb87 2 (1) 3Σg+ state

T. Takekoshi, Christoph Strauß, Florian J. W. Lang, Johannes Hecker Denschlag, Marius Lysebo, Leif Veseth

Published Jun 8, 2011• 19 citations
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Abstract

We present the results of an experimental and theoretical study of the electronically excited $(1){}^{3}{\ensuremath{\Sigma}}_{\mathrm{g}}^{+}$ state of $^{87}\mathrm{Rb}$${}_{2}$ molecules. The vibrational energies are measured for deeply bound states from the bottom up to ${v}^{\ensuremath{'}}=15$ using laser spectroscopy of ultracold Rb${}_{2}$ Feshbach molecules. The spectrum of each vibrational state is dominated by a 47-GHz splitting into ${0}_{\mathrm{g}}^{\ensuremath{-}}$ and ${1}_{\mathrm{g}}$ components caused mainly by a strong second-order spin-orbit interaction. Our spectroscopy fully resolves the rotational, hyperfine, and Zeeman structure of the spectrum. We are able to describe this structure to the first order using a simplified effective Hamiltonian.

DOI
10.1103/physreva.83.062504

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