Programme

P.40 -- Poster, VCTP-44

Date: Tuesday, 30 July 2019

Time: 08:30 - 10:00

Electric-field-enriched electronic and optical properties of Bernal stacked bilayer graphene nanoribbons

Thai Thanh Lap (1), Tran Minh Trung (2), Vu Thanh Tra (1), Tran Van Truong (3)

(1) Department of Physics, School of Education, Can Tho University, Can Tho, Vietnam; (2) School of Graduate, Can Tho University, Can Tho, Vietnam; (3) SRMP, CEA Saclay, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France.

We investigate the electronic and optical properties of Bernal stacked bilayer graphene nanoribbons under the effect of an external electric field using a combination of tight-binding model and the gradient approximation. Our results demonstrate that the electric field could modify significantly the low-energy dispersion, sub-band spacing, bandgap, and band-edge states. These effects are reflected clearly in the density of states and optical spectra. It indicates that the optical absorption spectra are sensitive to both the strength and direction of the electric field. The introduction of the electric field leads to substantial changes in the energy bands and wave functions, and thus creating new optical excitation channels. Additional absorption peaks are therefore explicitly observed.

Presenter: Vu Thanh Tra