Electronic transport in extended systems: Application to carbon nanotubes

We present an efficient approach to describe the electronic transport properties of extended systems. The method is based on the surface Green's function matching formalism and combines the iterative calculation of transfer matrices with the Landauer formula for the coherent conductance. The scheme is applicable to any general Hamiltonian that can be described within a localized orbital basis. As illustrative examples, we calculate transport properties for various ideal and mechanically deformed carbon nanotubes using realistic orthogonal and nonorthogonal tight-binding models. In particular, we observe that bent carbon nanotubes maintain their basic electrical properties even in the presence of large mechanical deformations.