2016/03/31 by Hazem Abdelsalam, H. Abdelsalam, M. H. Talaat +5 · 2 citations
Materials Science · Mathematics · Physics and Astronomy · #Absorption (acoustics) #Bilayer #Bilayer graphene #Chemical and Physical Properties of Materials #Electric field #Graph theory and applications #Graphene #Graphene research and applications #Quantum dot #Silicene #Zigzag #cond-mat.mes-hall
paper · pdf · doi:10.1063/1.4955222
published as J. Appl. Phys. 120, 014304 (2016) · 7 pages, 7 figures
openalex created_date 2016/06/24 · openalex publication_date 2016/07/06 · arxiv created 2017/08/25 · arxiv updated 2017/08/29 · openalex updated_date 2026/08/05
We study numerically the optical properties of low-buckled silicene and AB-stacked bilayer graphene quantum dots subjected to an external electric field, which is normal to their surface. Within the tight-binding model, the optical absorption is calculated for quantum dots, of triangular and hexagonal shapes, with zigzag and armchair edge terminations. We show that in triangular silicene clusters with zigzag edges a rich and widely tunable infrared absorption peak structure originates from transitions involving zero energy states. The edge of absorption in silicene quantum dots undergoes red shift in the external electric field for triangular clusters, whereas blue shift takes place for hexagonal ones. In small clusters of bilayer graphene with zigzag edges the edge of absorption undergoes blue/red shift for triangular/hexagonal geometry. In armchair clusters of silicene blue shift of the absorption edge takes place for both cluster shapes, while red shift is inherent for both shapes of the bilayer graphene quantum dots.