Solvent induced current-voltage hysteresis and negative differential resistance in molecular junctions

Abstract

We consider a single molecule circuit embedded into solvent. The Born dielectric solvation model is combined with Keldysh nonequilibrium Green's functions to describe the electron transport properties of the system. Depending on the dielectric constant, the solvent induces multiple nonequilibrium steady states with corresponding hysteresis in molecular current-voltage characteristics as well as negative differential resistance. We identify the physical range of solvent and molecular parameters where the effects are present. The position of the negative differential resistance peak can be controlled by the dielectric constant of the solvent.