Gap opening and transport in a graphene bilayer with selective functionalization

Ahmed Missaoui, Jouda Jemaa Khabthani, Nejm-Eddine Jaidane, Didier Mayou, Guy Trambly de Laissardière

Published 2017-12-01Version 1

In a Bernal graphene bilayer, carbon atoms belong to two inequivalent sublattices A and B, with atoms that are coupled to the other layer by $p_\sigma$ bonds belonging to sublattice A and the other atoms belonging to sublattice B. We analyze the density of states and the conductivity of Bernal graphene bilayers when atoms of sublattice A or B only are randomly functionalized. We find that for a selective functionalization on sublattice B only, a mobility gap of the order of 0.5 eV is formed close to the Dirac energy at concentration of adatoms $c\geq 10^{-2}$. In addition, at some other energies conductivity presents anomalous behaviors. We show that these properties are related to the bipartite structure of the graphene layer.