2014/10/28 by Smith, Dominik, Körner, Michael, von Smekal, Lorenz
#FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #Strongly Correlated Electrons (cond-mat.str-el)
paper · doi:10.48550/arxiv.1410.7601
We report on the status of ongoing Hybrid-Monte-Carlo simulations of the tight-binding model of mono-layer graphene. We present results concerning the semimetal-insulator phase transition, whereby two-body interactions are modeled by a partially screened Coulomb potential which takes into account screening by electrons in the lower σ-orbitals. We obtain evidence that finite-size effects may still be present in the current estimate of the critical coupling strength αC, which was previously extracted from simulations on lattice-sizes up to Nx=Ny=18. We also present preliminary results concerning the Neck-disrupting Lifshitz transition which occurs at finite Fermion-density in the limit of vanishing two-body interactions. A sign-problem is circumvented by using a spin-dependent chemical potential in our simulations.