Figure 1: Schematic of the lattice and band structure of the honeycomb lattice.
From: Unveiling pseudospin and angular momentum in photonic graphene

(a) Honeycomb lattice structure of graphene, where arrows illustrate the pseudospin representation of honeycomb sublattice (A or B) degree of freedom. (b) The band gap structure of graphene lattice exhibiting six Dirac points. (c) Zoom-in of the linear dispersion close to one of the Dirac points. (d) The first Brillouin zone of the lattice where the locations of two inequivalent corners are marked by K and K′.