Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Acoustic Phonon Dispersion Engineering in Bulk Crystals via
  Incorporation of Dopant Atoms   We report results of Brillouin - Mandelstam spectroscopy of transparent
alumina crystals with Nd dopants. The ionic radius and atomic mass of Nd atoms
are distinctively different from those of the host Al atoms. Our results show
that even a small concentration of Nd atoms incorporated into the alumina
samples produces a profound change in the acoustic phonon spectrum. The
velocity of the transverse acoustic phonons decreases by ~600 m/s at the Nd
density of only ~0.1 %. Interestingly, the decrease in the phonon frequency and
velocity with the doping concentration is non-monotonic. The obtained results,
demonstrating that modification of the acoustic phonon spectrum can be achieved
not only by nanostructuring but also by doping have important implications for
thermal management as well as thermoelectric and optoelectronic devices.

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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: physics
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: cmp-lg