Investigation of spatial current imaging in mesoscopic systems

We present a method for the numerical calculation of the spatial distribution of currents in mesoscopic quantum wires, based on the Keldysh-Green's function formalism. We adopt a lattice model and exploit the real space renormalization procedure to numerically describe a quantum point contact with the connecting leads. The computed conductance maps shed light on recent experiments aimed to probe the current distribution using scanning microscopy and open perspectives to design optimized device geometries.