Intrinsic plasmarons in warm graphene

Based on a self-consistent method, we predict theoretically that there exist intrinsic plasmarons in graphene at nonzero temperature, with a well defined mode, as shown by the result of Landau damping. We find that there are sharp differences between the discussed system and the QCD/QED system. Firstly, the thermal mass is proportional to ${\alpha }_g^{3/4}T$ but not ${\alpha }_{g}T$. Secondly, at $0<q<q_c$, the fermion channel and plasmaron channel are nearly degenerate, and furthermore the energy difference between fermion and plasmaron becomes larger and larger with increasing q in the region $q>q_c$. Thirdly, the fermion behaves as a 'relativistic particle' with nonzero mass, and the plasmaron exhibits an abnormal dispersion at moderate momentum. (paper)