Comparison of transport of edge states in 2D hexagonal lattice metallic, semiconducting and topological insulator nanoribbons

This study investigates the differences in electron transport properties between metallic, semiconducting and topological insulator nanoribbons (NRs). Using non-equilibrium Green’s function (NEGF) formalism, we have considered transport of edge states in four different scenarios. Metallic NRs show Klein tunneling in the presence of barrier. Topological insulator NRs show Klein tunneling in the presence of barrier and robust transport in the presence of ‘Cut’ and edge roughness. As expected, the semiconducting NRs do not show any special transport property.