Localization and nonlinear transport in disordered electronic chain driven out of equibrium.

Quenched disorder in a solid state system leads to Anderson localization which stops electron movement and renders the solid to behave as an insulator. In this work, we discuss the effect of a DC electric field on Anderson localization on a simple tight binding chain with level disorder using a full lattice calculation of the Green's function and the Coherent potential approximation. In the linear transport regime Mott's 1/2-law for variable range hopping transport is emergent in our model. In the presence of electric fields, the system shows gradual crossover from Anderson localization to Wannier Stark localization. At high disorder, there is disorder induced insulator to metal transition as the average band edge broadens which is verified using the CPA approach. Our finite lattice calculations show disorder range for variable range hopping that is marked by increase in hopping length and the mobility of electrons with electric field. We show a scaling behavior of the conductance with electric field, similar to the Mott's variable range hopping in a disordered chain kept out of equilibrium.