Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Overscreened Kondo effect, (color) superconductivity and Shiba states in
  Dirac metals and quark matter   We study the interplay between the Kondo effect and (color) superconductivity
in doped Dirac metals with magnetic impurities and in quark matter with
colorful impurities. We first point out that the overscreened Kondo effect
arises in the normal state of these systems. Next the (color) superconducting
gap is incorporated as a mean field and the phase diagram for a varying gap and
temperature is constructed nonperturbatively. A rich phase structure emerges
from a competition of effects unique to a multichannel system. The
Kondo-screened phase is shown to disappear for a sufficiently large gap.
Peculiarity of quark matter due to the confining property of non-Abelian gauge
fields is noted. We also investigate the spectrum of sub-gap excited states,
called Shiba states. Based on a model calculation and physical reasoning we
predict that, as the coupling of the impurity to the bulk is increased, there
will be more than one quantum phase transition due to level crossing among
overscreened states.

27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
2
The categories of this paper are: math