• DOI:10.1103/PhysRevLett.118.026403
• Corpus ID: 29355448

Stability of Dirac Liquids with Strong Coulomb Interaction.

@article{Tupitsyn2016StabilityOD,
  title={Stability of Dirac Liquids with Strong Coulomb Interaction.},
  author={Igor S. Tupitsyn and Nikolay V. Prokof’ev},
  journal={Physical review letters},
  year={2016},
  volume={118 2},
  pages={
          026403
        }
}

• I. Tupitsyn, N. Prokof’ev
• Published 30 July 2016
• Physics
• Physical review letters

We develop and apply the diagrammatic Monte Carlo technique to address the problem of the stability of the Dirac liquid state (in a graphene-type system) against the strong long-range part of the Coulomb interaction. So far, all attempts to deal with this problem in the field-theoretical framework were limited either to perturbative or random phase approximation and functional renormalization group treatments, with diametrically opposite conclusions. Our calculations aim at the approximation-free solution with controlled accuracy by computing vertex corrections from higher-order skeleton diagrams and establishing the renormalization group flow of the effective Coulomb coupling constant. We unambiguously show that with increasing the system size L (up to ln(L)∼40), the coupling constant always flows towards zero; i.e., the two-dimensional Dirac liquid is an asymptotically free T=0 state with divergent Fermi velocity.