Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Phonon Optics: Coherent and Squeezed Atomic Displacements   In this paper we investigate coherent and squeezed quantum states of phonons.
The latter allow the possibility of modulating the quantum fluctuations of
atomic displacements below the zero-point quantum noise level of coherent
states. The expectation values and quantum fluctuations of both the atomic
displacement and the lattice amplitude operators are calculated in these
states---in some cases analytically. We also study the possibility of squeezing
quantum noise in the atomic displacement using a polariton-based approach.

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The categories of this paper are: eess
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
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The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
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The categories of this paper are: funct-an
30
The categories of this paper are: q-alg