Quasiparticle renormalization inABCgraphene trilayers

Abstract

We investigate the effect of electron-electron interactions in $ABC$-stacked graphene trilayers. In the gapless regime, we show that the self-energy corrections lead to the renormalization of the dynamical exponent $z=3+{\ensuremath{\alpha}}_{1}/N$, with ${\ensuremath{\alpha}}_{1}\ensuremath{\approx}0.52$ and $N$ is the number of fermionic species. Although the quasiparticle residue is suppressed near the neutrality point, the lifetime has a sublinear scaling with the energy and the quasiparticles are well defined even at zero energy. We calculate the renormalization of a variety of physical observables, which can be directly measured in experiments.