At present, two different software packages are being developed:
- ALACANT: This is a project started in the year 2000 at the Physics Department of the University of Alicante with the aim to compute the electrical current in atomically-defined nanostructures combining Density Functional Theory and the non-equilibrium Green's functions formalism (Landauer/Keldysh). It interfaces the popular quantum-chemistry GAUSSIAN03 and it is specifically designed for the computation of the coherent electron transmission and resulting electrical current in all-metal atomic contacts or molecular bridges as created by a variety of scanning tunneling microscope or break junctions techniques. This naturally includes the computation and simulation of scanning tunneling microscopy images. It follows an onion shell structure, modeling the far electrodes as a parametrized Bethe lattice while making a fully first-principles description towards the system core.
- ANT: It is specifically designed for the computation of the coherent electron transmission and resulting electrical current in quasi-one-dimensional systems such as atomic chains, nanowires, and carbon nanotubes. It works as a post-processing procedure to a periodic boundary conditions calculation (e.g., with CRYSTAL06). It thus uses a pre-computed Hamiltonian for the device core and for the electrodes in the form of finite-section wires.