Vacancy-induced shifts of edge states in Z-shaped graphene nanoribbon quantum dot. (October 2017)

• Record Type: Journal Article
• Authors: Kihira, Kazuma; Aoki, Masato
• Is Part Of: Materials research bulletin. Volume 94(2017)
• Page Start: 208
• Page End: 215
• Publication Date: 2017-10
• Subjects: Nanostructures -- Semiconductors -- Thin films -- Defects -- Electronic structure; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2017.06.006
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Effects of a vacancy in the Z-shaped GNR junction are predicted theoretically. Edge states, zero-mode states and dangling bond states are discussed. The transmission of the system is discussed. The energy separation of edge states can vary with the choice of a vacancy site. Abstract: Quasi-one-dimensional quantum dot consisting of Z-shaped graphene nanoribbon junction, is known to create discrete edge states in the bandgap due to quantum confinement effect depending on the length of the quantum dot. To examine possible changes in the midgap states caused by introducing a carbon vacancy within the quantum dot, we calculated the band structures of the defective systems using density functional based tight-binding method, and also using a simplest tight-binding model for π -electrons. As the central result, we predict that the separation of midgap edge states are considerably variable, depending on the choice of a vacancy site. The transmission via midgap edge states and zero-mode state is shown.