▎ 摘　　要

The field of plasmonics relies on light coupling strongly to plasmons as collective excitations. The energy loss function of graphene is dominated by two peaks at similar to 5 and similar to 45 eV, known as pi and pi + sigma plasmons, respectively. We use electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope and density functional theory to show that between 1 to 50 eV, these prominent pi and pi + sigma peaks are not plasmons, but single-particle interband excitations.