Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Preparation of Dicke States in an Ion Chain   We have investigated theoretically and experimentally a method for preparing
Dicke states in trapped atomic ions. We consider a linear chain of $N$ ion
qubits that is prepared in a particular Fock state of motion, $|m>$. The $m$
phonons are removed by applying a laser pulse globally to the $N$ qubits, and
converting the motional excitation to $m$ flipped spins. The global nature of
this pulse ensures that the $m$ flipped spins are shared by all the target ions
in a state that is a close approximation to the Dicke state $\D{N}{m}$. We
calculate numerically the fidelity limits of the protocol and find small
deviations from the ideal state for $m = 1$ and $m = 2$. We have demonstrated
the basic features of this protocol by preparing the state $\D{2}{1}$ in two
$^{25}$Mg$^+$ target ions trapped simultaneously with an $^{27}$Al$^+$
ancillary ion.

20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
8
The categories of this paper are: hep-ex
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn
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The categories of this paper are: econ