Figure 2: Calculated optical response of 7-AGNRs.
From: Exciton-dominated optical response of ultra-narrow graphene nanoribbons
(a) Optical absorption spectrum and electronic band structure of 7-AGNRs calculated from first principles within the GW-BSE approach. The blue bars indicate the energy position and oscillator strength of the calculated optical excitations. The spectrum was obtained with a broadening of 0.5 eV and the same spectral lineshape used for fitting the RDS data (see Methods). The absolute absorbance for full coverage and light polarized along the longitudinal (x) direction is also shown (orange curve), as compared with the reference value of 2.3% for ML graphene (dotted orange line). (b) Exciton wavefunctions of the first and second excitons for 7-AGNRs. The calculated electron distribution is shown at fixed hole position (black dot). (c) Schematics of the relations between transport and optical gaps determined by STS and RDS, as compared with ab-initio calculations in vacuum.
