Extended Data Fig. 5: Plasmon mode in AB stacked bilayer graphene.
From: Observation of chiral and slow plasmons in twisted bilayer graphene
a, Extinction spectra of AB stacked bilayer graphene. Graphene flake is patterned to spiral nanoribbon arrays whose width ranges from 100 to 200 nm. The three branches of mid-energy plasmon are marked. The dashed lines indicate silica SO phonon and graphene optical phonon, respectively. b, Plasmon peak (peak 1 of the 200 nm sample) intensity as a function of the polarization detection angle. c, SEM image of a typical spiral nanoribbon made of AB stacked graphene. Scale bar 200 nm.
