2009/10/29 by Wesley Armour, Wes Armour, Simon Hands +1 · 1 citation
Materials Science · Physics and Astronomy · #Condensed matter physics #Critical exponent #Critical phenomena #Dirac fermion #Graphene #Graphene research and applications #Materials science #Monolayer #Monte Carlo method #Mott insulator #Nanotechnology #Phase transition #Physics #Quantum Monte Carlo #Quantum and electron transport phenomena #Quantum critical point #Quantum mechanics #Quantum phase transition #Quasiparticle #Topological Materials and Phenomena #cond-mat.str-el #hep-lat
paper · pdf · doi:10.1103/physrevb.81.125105
published as Phys.Rev.B81:125105,2010 · 19 pages
arxiv created 2009/10/29 · openalex publication_date 2010/03/04 · arxiv updated 2010/04/29 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
A 2+1-dimensional fermion field theory is proposed as a model for the low-energy electronic excitations in monolayer graphene. The model consists of Nf=2 four-component Dirac fermions moving in the plane and interacting via a contact interaction between charge densities. For strong couplings there is a continuous transition to a Mott insulating phase. We present results of an extensive numerical study of the model's critical region, including the order parameter, its associated susceptibility, and the quasiparticle propagator. The data enable an extraction of the critical exponents at the transition (including the dynamical critical exponent) which are hypothesized to be universal features of a quantum critical point. The relation of our model with others in the literature is discussed along with the implications for physical graphene following from our value of the critical coupling.