arXiv:1001.0123v1 [cond-mat.mes-hall] 31 Dec 2009 $^{1}$Theoretical Condensed Matter Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata-700 064, India $^{2}$Department of Physics, Narasinha Dutt College, 129 Belilious Road, Howrah-711 101, India Santanu K. Maiti 1 , $^{2}$,1 Quantum transport in honeycomb lattice ribbons with zigzag edges: A theoretical study Abstract We explore electron transport properties in honeycomb lattice ribbons with zigzag edges coupled to two semi-infinite one-dimensional metallic electrodes. The calculations are based on the tight-binding model and the Green’s function method, which numerically compute the conductance-energy and current-voltage characteristics as functions of the lengths and widths of the ribbons. Our numerical results predict that for such a ribbon an energy gap always appears in the conductance spectrum across the energy E = 0. With the increase of the size of the ribbon, the gap gradually decreases but it never vanishes. This clearly manifests that a honeycomb lattice ribbon with zigzag edges always exhibits the semiconducting behavior, and it becomes much more clearly visible from our presented current-voltage characteristics. PACS No. : 73.63.-b; 73.63.Rt. Keywords : Honeycomb lattice ribbon; Zigzag edges; Conductance; I - V characteristic. $^{1}$Corresponding Author : Santanu K. Maiti Electronic mail: santanu.maiti@saha.ac.in 1