Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Singlet Pathway to the Ground State of Ultracold Polar Molecules   Starting from weakly bound Feshbach molecules, we demonstrate a two-photon
pathway to the dipolar ground state of bi-alkali molecules that involves only
singlet-to-singlet optical transitions. This pathway eliminates the search for
a suitable intermediate state with sufficient singlet-triplet mixing and the
exploration of its hyperfine structure, as is typical for pathways starting
from triplet dominated Feshbach molecules. By selecting a Feshbach state with a
stretched singlet hyperfine component and controlling the polarization of the
excitation laser, we assure coupling to only a single hyperfine component of
the $\textrm{A}^{1}\Sigma^{+}$ excited potential, even if the hyperfine
structure is not resolved. Similarly, we address a stretched hyperfine
component of the $\textrm{X}^{1}\Sigma^{+}$ rovibrational ground state, and
therefore an ideal three level system is established. We demonstrate this
pathway with ${}^{6}\textrm{Li}{}^{40}\textrm{K}$ molecules. By exploring
deeply bound states of the $\textrm{A}^{1}\Sigma^{+}$ potential, we are able to
obtain large and balanced Rabi frequencies for both transitions. This method
can be applied to other molecular species.

14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
2
The categories of this paper are: math
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The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
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The categories of this paper are: solv-int
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The categories of this paper are: q-fin