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arXiv · 1405.1962

Gaussian deformations in graphene ribbons: flowers and confinement

R. Carrillo-Bastos·D. Faria·A. Latgé·F. Mireles·N. Sandler
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Abstract

The coupling of geometrical and electronic properties is a promising venue to engineer conduction properties in graphene. Confinement added to strain allows for interplay of different transport mechanisms with potential device applications. To investigate strain signatures on transport in confined geometries, we focus on graphene nanoribbons (GNR) with circularly symmetric deformations. In particular, we study GNR with an inhomogeneous, out of plane Gaussian deformation, connected to reservoirs. We observe an enhancement of the density of states in the deformed region, accompanied with a decrease in the conductance, signaling the presence of confined states. The local density of states exhibits a six-fold symmetric structure with an oscillating sub-lattice occupation asymmetry, that persist for a wide range of energy and model parameters.

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R. Carrillo-Bastos, D. Faria, A. Latgé, F. Mireles, N. Sandler. 2014-05-08. Gaussian deformations in graphene ribbons: flowers and confinement. https://doi.org/10.1103/physrevb.90.041411

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