Quasiparticle Energies and Optical Excitations in Chevron-Type Graphene Nanoribbon

The electronic structure and optical properties of very recently synthesized chevron-type graphene nanoribbon (CGNR) are investigated within many-body Green’s function and Bethe–Salpeter equation formalism. The CGNR can effectively confine both electrons and holes, leading to its exciton binding energy larger than that of regular GNRs. The excitonic peaks owing to electron–hole interactions dominate the optical spectra with a significant blue-shift and a different line shape in CGNR compared with those in regular GNRs. Moreover, the singlet–triplet exciton splitting of CGNR is also larger than that of the regular GNRs, which is expected to show high fluorescence luminescence efficiency. The enhanced excitonic effects in CGNR should be of great importance in optoelectronic applications.