Abstract

Electron tunneling through a two-stage Kondo system constituted by a double quantum dot molecule side coupled to a quantum wire under the effect of a finite external potential is studied. We found that I-V characteristic shows a negative differential conductance region induced by the electronic correlation. This phenomenon is a consequence of the properties of the two-stage Kondo regime under the effect of an external applied potential that takes the system out of equilibrium. The problem is solved using the mean-field finite- U slave-boson formalism. © 2008 The American Physical Society.