Polarization-induced switching effect in graphene nanoribbon edge-defect junction

Abstract

With nonequilibrium Green's function approach combined with density functional theory, we perform an ab initio calculation to investigate transport properties of graphene nanoribbon (GNR) junctions self-consistently. Tight-binding approximation is applied to model the zigzag (ZGNR) electrodes, and its validity is confirmed in comparison to the GAUSSIAN03 periodic boundary condition calculation result of the same system. The origin of abnormal jump points usually appearing in the transmission spectrum is explained with the detailed tight-binding ZGNR band structure. Transport property of an edge-defect ZGNR junction is investigated, and the tunable tunneling current can be sensitively controlled by transverse electric fields.

Hydrogenation-chain-opened conductive channels in zigzag graphene nanoribbons

“…28 The p electron's property is affected by the topological structure, while the bonding length between carbon atoms in the edges is elongated compared with central atoms. 29 This work is intended to study the role of edge states in the process of electronic transport by hydrogenation in ZGNRs. In order to enhance the conduction of the graphene nanoribbons, we design modified nanoribbons with one or two carbon chains hydrogenated on opposite faces of the nanoribbon sheet.…”

“…The tightbinding (TB) periodic unit cell of ZGNR includes two armchair carbon atom chains to avoid crucial inter-cell interacting information loss. 29 The numerical basis set describing the valence electrons and the core electrons in carbon atoms are modeled by norm-conserving TroullierMartins pseudopotentials. 33 We adapt the double-zeta polarization (DZP) basis set for valence electrons for accuracy.…”

Edge state effects in junctions with graphene electrodes

“…1), where a molecule is coupled to the graphene edges (here a variety of molecules and anchoring groups can be used). The theoretical investigation of such structures was started recently for all-carbon junctions [12][13][14][15][16][17][18][19][20] and junctions with different organic molecules. [21][22][23][24] In particular, one example is the experimental 6,7 and theoretical 6,14,[16][17][18] investigations of linear atomic carbon chains between single-layer graphene electrodes and the first experimental observation of the current through the molecular junction with few-layer electrodes.…”

Electronic and spin transport properties of a benzene molecule connected to graphene leads

“…Also, the transport properties of single molecule magnets (SMMs) are attractive for high density data storage and quantum computing 6–9. Since an organic molecule (1,4‐benzenedithiol) has been bridged by two gold electrodes in 1997 10, many theoretical and experimental studies have been done for understanding the properties of molecular electronics 11–13. In molecular electronics, when the leads are made of metals such as gold, people should consider a three‐dimensional structure, such as face centered cubic, when they calculate the electronic transport properties 14–16.…”