Is suspended graphene an insulator

Graphene shares many features with relativistic theories of fermions, as the low-energy degrees of freedom are Dirac quasiparticles with linear dispersion. However, unlike the case of Quantum Electrodynamics, the quasiparticles in graphene are strongly coupled, such that the fine strcture constant in graphene is ~1, which poses a challenging many-body problem. At such strong coupling, the appearance of a gapped state in the electronic phase diagram of graphene is a real possibility, due to spontaneous pairing of particles and holes. I will discuss such an excitonic gap in graphene in the light of recent Lattice Monte Carlo simulations and experimental results.