Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum criticality in the metal-superconductor transition of
  interacting Dirac fermions on a triangular lattice   We investigate a semimetal-superconductor phase transition of two-dimensional
Dirac electrons at zero temperature by large-scale and essentially unbiased
quantum Monte Carlo simulations for the half-filled attractive Hubbard model on
the triangular lattice, in the presence of alternating magnetic $\pi$-flux,
that is introduced to construct two Dirac points in the one-particle bands at
the Fermi level. This phase transition is expected to describe quantum
criticality of the chiral XY class in the framework of the Gross-Neveu model,
where, in the ordered phase, the $U(1)$ symmetry is spontaneously broken and a
mass gap opens in the excitation spectrum. We compute the order parameter of
the s-wave superconductivity and estimate the quasiparticle weight from the
long-distance behavior of the single-particle Green's function. These
calculations allow us to obtain the critical exponents of this transition in a
reliable and accurate way. Our estimate for the critical exponents is in good
agreement with those obtained for a transition to a Kekul\'{e} valence bond
solid, where an emergent $U(1)$ symmetry is proposed [Z.-X. Li et al., Nat.
Commun. 8, 314 (2017)].

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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
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The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg