Negative differential conductance induced by electronic correlation in a double quantum-dot molecule

TL;DR

This paper investigates how electronic correlations in a double quantum-dot molecule cause negative differential conductance in electron tunneling, especially under external bias, using a mean-field slave-boson approach.

Contribution

It demonstrates that the two-stage Kondo effect under external potential leads to negative differential conductance, revealing new insights into correlated quantum dot systems.

Findings

Negative differential conductance observed in the I-V characteristics.

Correlation effects induce non-trivial transport behavior.

External potential influences the Kondo regime and conductance.

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.