Role of edge reconfiguration in generating corner states in Zigzag graphene nanoribbons

Abstract

The study investigates the significance of edge architecture in graphene nanoribbons and its implications on electronic properties and transport behavior. Particularly, it explores the effects of edge reconstruction on Zigzag graphene nanoribbons, focusing on the impact of (5, 7) edge remodeling caused by Stone–Wales defects on topological features and edge states. The energy band structure and state distribution of the reconfigured Zigzag (5, 7) graphene nanoribbon were examined using the tight-binding model. The findings indicate that the edge reconstruction creates energy gaps in the edge-state bands, resulting in the appearance of corner states at the vertices of rectangular graphene nanoflakes with reconstructed edges. Furthermore, analysis of the boundary atomic structure unveiled an SSH4-like configuration at the edges, forming a topological structure that gives rise to zero-energy corner states and two distinct nonzero-energy corner states. The study also notes a transition of non-zero energy corner states towards zero energy influenced by bulk and edge states, while zero-energy corner states shift towards non-zero energy and some merge with the edge states. Nevertheless, the impact of the staggered potential largely restores the corner states determined by the edge structure. This research underscores the significant implications of Stone–Wales-deficient reconfiguration on the topological properties and edge states of Zigzag graphene nanoribbons, providing a theoretical basis for tailoring electron transport characteristics and guiding the development of advanced optoelectronic devices.