Shot noise in strongly correlated double quantum dots

Rosa López, Ramón Aguado, and Gloria Platero
Phys. Rev. B 69, 235305 – Published 7 June 2004

Abstract

We have investigated theoretically the shot noise of strongly correlated double quantum dot systems in the regime where the Kondo effect and the interdot antiferromagnetic exchange do compete. Our calculations are based on a generalization to nonequilibrium transport of the two-impurity Anderson Hamiltonian which is solved by the slave-boson mean-field theory. This mean-field approach together with nonequilibrium Green’s-function techniques allow us to obtain closed formulas for the shot noise in the strong-coupling regime. Two configurations are considered: series and parallel. When the two quantum dots are in series, we obtain at low voltages, a nonmonotonic behavior of the Fano factor, as a function of the interdot tunneling coupling. When the competition between the Kondo effect and the interdot antiferromagnetic exchange starts to play a role this picture is strongly modified. In a parallel configuration, the functional form of the Fano factor as a function of the applied voltage Vdc changes abruptly, depending on whether the ratio between the antiferromagnetic exchange constant J and the Kondo temperature TK is below or above (JTK)c2.5. Below (JTK)c, the Fano factor behaves as in the single quantum dot case (monotonic dependence which saturates at large voltages). Above (JTK)c, the Fano factor exhibits a nonmonotonic dependence on voltage, with a kink at eVdc=J.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 9 May 2003

DOI:https://doi.org/10.1103/PhysRevB.69.235305

©2004 American Physical Society

Authors & Affiliations

Rosa López1,2, Ramón Aguado2, and Gloria Platero2

  • 1Département de Physique Théorique, Université de Genève, CH-1211 Genève 4, Switzerland
  • 2Teoría de la Materia Condensada, Instituto de Ciencia de Materiales de Madrid, (CSIC) Cantoblanco, 28049 Madrid, Spain

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 69, Iss. 23 — 15 June 2004

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×