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Four-loop critical exponents for the Gross-Neveu-Yukawa models

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 نشر من قبل Michael M. Scherer
 تاريخ النشر 2017
  مجال البحث فيزياء
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We study the chiral Ising, the chiral XY and the chiral Heisenberg models at four-loop order with the perturbative renormalization group in $4-epsilon$ dimensions and compute critical exponents for the Gross-Neveu-Yukawa fixed points to order $mathcal{O}(epsilon^4)$. Further, we provide Pade estimates for the correlation length exponent, the boson and fermion anomalous dimension as well as the leading correction to scaling exponent in 2+1 dimensions. We also confirm the emergence of supersymmetric field theories at four loops for the chiral Ising and the chiral XY models with $N=1/4$ and $N=1/2$ fermions, respectively. Furthermore, applications of our results relevant to various quantum transitions in the context of Dirac and Weyl semimetals are discussed, including interaction-induced transitions in graphene and surface states of topological insulators.

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