Bandstructure and quantum transport properties of AGNR unit cells with V-shaped edge patterning

We investigate how the electronic and transport properties of six arm-chair graphene nanoribbon-based structures are modified with the introduction of symmetrical and asymmetrical geometrical V-cuts on their edges. A tight-binding model based on numerical non-equilibrium Green’s function method is used to compute the transport properties such as local density of states, transmission and current–voltage characteristics. We report the existence of nearly flat mid-bands for certain topologies after edge patterning. These bands give rise to non-zero transmission at low bias voltages. We uncover how this transmission varies with width, length, and biasing of the channel and also the temperature of the contacts. For structures in which flat mid-bands are absent, we show how their band gaps could be tuned by varying the width and length of the modified unit cells.