Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transition from a strong-coupling fixed point to an
  intermediate-coupling fixed point in a single-channel SU(N) Kondo model: role
  of the filling and two-stage screening   We study an extended SU(N) single-impurity Kondo model in which the impurity
spin is described by a combination of Abrikosov fermions and Schwinger bosons.
Our aim is to describe both the quasiparticle-like excitations and the locally
critical modes observed in various physical situations, including non-Fermi
liquid behavior in heavy fermion systems in the vicinity of a quantum critical
point. We identify the strong coupling fixed point of the model and study its
stability within second order perturbation theory. Already in the single
channel case and in contrast with either the pure bosonic or the pure fermionic
case, the strong coupling fixed point is unstable against the conduction
electron kinetic term as soon as the amount of Abrikosov fermions reaches a
critical value. In the stability region, the partially screened, dressed
impurity at site 0 repels the conduction electrons on adjacent sites. In the
instability region, the impurity tends to attract $(N-1)$ conduction electrons
to the neighboring sites, giving rise to a two-stage Kondo effect with
additional screening.This result opens the route to the existence of an
intermediate coupling fixed point, characterized by non-Fermi liquid behavior.

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The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: quant-ph
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The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
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The categories of this paper are: astro-ph
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The categories of this paper are: chem-ph
3
The categories of this paper are: physics