Electronic transport in polycrystalline graphene

Abstract

Most materials in available macroscopic quantities are polycrystalline. Graphene, a recently discovered two-dimensional form of carbon with strong potential for replacing silicon in future electronics, is no exception. There is growing evidence of the polycrystalline nature of graphene samples obtained using various techniques. Grain boundaries, intrinsic topological defects of polycrystalline materials, are expected to dramatically alter the electronic transport in graphene. Here, we develop a theory of charge carrier transmission through grain boundaries composed of a periodic array of dislocations in graphene based on the momentum conservation principle. Depending on the grain boundary structure we find two distinct transport behaviours - either high transparency, or perfect reflection of charge carriers over remarkably large energy ranges. First-principles quantum transport calculations are used to verify and further investigate this striking behaviour. Our study sheds light on the transport properties of large-area graphene samples. Furthermore, purposeful engineering of periodic grain boundaries with tunable transport gaps would allow for controlling charge currents without the need of introducing bulk band gaps in otherwise semimetallic graphene. The proposed approach can be regarded as a means towards building practical graphene electronics.

accepted in Nature Materials

References in corpus (9)

• The electronic properties of graphene
• Chiral tunneling and the Klein paradox in graphene
• Graphene field-effect-transistors with high on/off current ratio and large transport band gap at room temperature
• Quantum interference and Klein tunneling in graphene heterojunctions
• Topological Defects in Graphene: Dislocations and Grain Boundaries
• Evidence of Klein tunneling in graphene p-n junctions
• Self-passivating edge reconstructions of graphene
• Room-temperature ferromagnetism in graphite driven by 2D networks of point defects
• Cones, pringles, and grain boundary landscapes in graphene topology

Cited by in corpus (7)

• Control and Characterization of Individual Grains and Grain Boundaries in Graphene Grown by Chemical Vapor Deposition
• From Point Defects in Graphene to Two-Dimensional Amorphous Carbon
• Graphene valley filter using a line defect
• Tuneable electronic properties in graphene
• Grain Boundary Loops in Graphene
• Graphene: Piecing it together
• Revealing the grain structure of graphene grown by chemical vapor deposition