Electron transport in quantum antidots made of four-terminal graphene ribbons

Abstract

Electronic and transport properties of two-and four-terminal graphene nanoribbons are studied taking into account different configurations of quantum antidot potentials, designed at a central conductor. Local density of states maps the electronic distribution changes induced by the antidot potentials and highlights localization effects at the neighboring vacancy sites. Depending on the position, extension, and symmetry of such antidots, we found delocalization of electronic states leading to particular conduction paths along the central region. The origin of dips and maxima in the conductance, and full transport suppression was studied within a microscopic scenario using real-space Green function formalism. The combination of antidot potentials and extra terminals in the device model has shown to generate a variety of transport responses that may be experimentally tuned.

Novel properties of graphene nanoribbons: a review

“…56 Another interesting class of materials, known as graphene antidots, has emerged in recent times with interesting electronic structures and edge states. [239][240][241][242][243] Graphane, the sp 3 hybridized analogue of graphene has been observed experimentally very recently. 244 The integrated graphene-graphane structure has been predicted to show interesting device applications.…”

Bandgap Opening in Graphene Antidot Lattices: The Missing Half

“…It possesses great potential applications in many emerging areas such as next-generation ultrahigh performance electronics and transistor logic circuits, sensors, and transparent conductors. − Several schemes have been proposed to open a tunable bandgap in graphene, which is required for semiconductor materials. ,− Recently, a strategy of constructing periodic holes on graphene to form graphene antidot lattices (GALs) has been extensively studied. − Theoretical calculations have predicted that antidot lattices change the electronic properties of graphene from semimetallic to semiconducting, where the opened gap can be tuned by the size, shape, and symmetry of both the hole and the lattice cell. − ,− The induced gap in GALs is approximately proportional to the hole diameter and inversely proportional to the superlattice cell area, so one can achieve a substantial gap value of ∼0.2 eV in a unit cell of 10 nm . Accordingly, the transport properties of graphene nanoribbons (GNRs) are modulated by the existence of the antidots. − Antidot lattices on graphene also affect the occurrence of flat bands and collective magnetic behavior, and thus may lead to applications in storage media and spintronics. ,,− Alternative periodic perturbations by such means as selective adsorption and nanohubs have also been explored theoretically. − …”

Multi-terminal magneto-transport in an interacting fractal network: a mean field study

“…Electronic transport in low dimensional systems is a key to explore important interference effects, local currents, switching mechanisms and other unique properties that are pre-requisites for estimating the potentiality of these systems as quantum interference devices [1][2][3]. A considerable amount of work in this direction has already revealed the unique features of phase coherent electron transport through quantum dots (QD), Aharonov-Bohm (AB) rings, and model molecular systems [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”

“…Comparatively speaking, much smaller volume of literature on the three or four terminal electronic transport have come up in recent times [11][12][13][14][15][16][17][18]. A two-terminal device is essentially a single path device.…”