Scanning-gate-induced effects in nonlinear transport through nanostructures

Cosimo Gorini (1, 2) , Dietmar Weinmann (2) , Rodolfo A. Jalabert (2)

1 SPEC - UMR3680 - Service de physique de l'état condensé
2 IPCMS - Institut de Physique et Chimie des Matériaux de Strasbourg

We investigate the effect of a scanning gate tip in the nonlinear quantum transport properties of nanostructures. Generally, we predict that the symmetry of the current-voltage characteristic in reflection-symmetric samples is broken by a tip-induced rectifying conductance correction. Moreover, in the case of a quantum point contact (QPC), the tip-induced rectification term becomes dominant as compared to the change of the linear conductance at large tip-QPC distances. Calculations for a weak tip probing a QPC modeled by an abrupt constriction show that these effects are experimentally observable.

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Cosimo Gorini, Dietmar Weinmann, Rodolfo A. Jalabert. Scanning-gate-induced effects in nonlinear transport through nanostructures. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2014, 89, pp.115414. ⟨10.1103/PhysRevB.89.115414⟩. ⟨hal-00961023⟩