Double-periodic quasi-periodic graphene superlattice: non-Bragg band gap and electronic transport

TL;DR

This paper investigates electronic band gaps and transport in a quasi-periodic graphene superlattice, revealing a robust zero-$ar{k}$ gap linked to an unusual Dirac point, with implications for graphene electronics.

Contribution

It introduces the concept of a zero-$ar{k}$ gap in double-periodic quasi-periodic graphene superlattices and analyzes its robustness and relation to Dirac points.

Findings

Zero-$ar{k}$ gap is less sensitive to incidence angle.

Zero-$ar{k}$ gap is robust against lattice constant variations.

Control of electron transport over the zero-$ar{k}$ gap is demonstrated.

Abstract

Electronic band gap and transport in quasi-periodic graphene superlattice of double-periodic sequence have been investigated. It is found that such quasi-periodic structure can possess a zero-averaged wave number (zero-$\bar{k}$) gap which associated with an unusual Dirac point. Different from Bragg gap, the zero-$\bar{k}$ gap is less sensitive to the incidence angle, and robust against the lattice constants. The locations of Dirac point and multi-Dirac-points in the graphene superlattices of various sequences are also compared. The control of electron transport over the zero-$\bar{k}$ band gap in graphene superlattice may facilitate the development of many graphene-based electronics.