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Motivated by the puzzling optical conductivity measurements in graphene, we
speculate on the possible role of strong electronic correlations on the two-dimensional Dirac
fermions. In this work we employ the slave-particle method to study the excitations of the
Hubbard model on honeycomb lattice, away from half-filling. Since the ratio $U/t\approx 3.3$ in
graphene is not infinite, double occupancy is not entirely prohibited and hence a finite density
of doublons can be generated. We therefore extend the Ioff-Larkin composition rule to include
a finite density of doublons. We then investigate the role played by each of these auxiliary
particles in the optical absorption of strongly correlated Dirac fermions.
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