Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phonon-induced electronic relaxation in a strongly correlated system:
  the Sn/Si(111) $(\sqrt 3 \times \sqrt 3)$ adlayer revisited   The ordered adsorbate layer Sn/Si(111) $(\sqrt 3 \times \sqrt 3)$ with
coverage of one third of a monolayer is considered as a realization of strong
electronic correlation in surface physics. Our theoretical analysis shows that
electron-hole pair excitations in this system can be long-lived, up to several
hundred nanoseconds, since the decay into surface phonons is found to be a
highly non-linear process. We combine first-principles calculations with help
of a hybrid functional (HSE06) with modeling by a Mott-Hubbard Hamiltonian
coupled to phononic degrees of freedom. The calculations show that the
Sn/Si(111) $(\sqrt 3 \times \sqrt 3)$ surface is insulating and the two
Sn-derived bands inside the substrate band gap can be described as the lower
and upper Hubbard band in a Mott-Hubbard model with $U=0.75$eV. Furthermore,
phonon spectra are calculated with particular emphasis on the Sn-related
surface phonon modes. The calculations demonstrate that the adequate treatment
of electronic correlations leads to a stiffening of the wagging mode of
neighboring Sn atoms; thus, we predict that the onset of electronic
correlations at low temperature should be observable in the phonon spectrum,
too. The deformation potential for electron-phonon coupling is calculated for
selected vibrational modes and the decay rate of an electron-hole excitation
into multiple phonons is estimated, substantiating the very long lifetime of
these excitations.

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The categories of this paper are: econ
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
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The categories of this paper are: astro-ph
15
The categories of this paper are: nucl-ex
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The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
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The categories of this paper are: dg-ga
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The categories of this paper are: math
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: nucl-th
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int