Current-Voltage characteristics of the Azo-benzene nano-molecular wires from first principles

Using Density Functional Non-Equilibrium Green’s Function (DFT-NEGF) method we perform a detailed study of the transport properties of a novel light-driven molecular switch. We consider two isomers of Azo-benzene moleculular wires, Cis and Trans, sandwiched between two Au (1 0 0) electrodes. It has been found that the conductance of the cis isomer is significantly smaller than that of the trans one. Thus, whenever the Azo-benzene is made to flip from the cis conformation to the trans conformation, the wire is predicted to switch from a weakly conducting to a highly conducting state. The transmission coefficients T (E) of the two-probe system at zero bias have also been analyzed.