Nonequilibrium transport through double quantum dots: Kondo effect versus antiferromagnetic coupling.
We theoretically study the nonequilibrium transport properties of double quantum dots, in both series and parallel configurations. Our results lead to novel experimental predictions that unambiguously signal the transition from a Kondo state to an antiferromagnetic spin-singlet state, directly reflecting the physics of the two-impurity Kondo problem. We prove that the nonlinear conductance through parallel dots directly measures the exchange constant J between the spins of the dots. In serial dots, the nonlinear conductance provides an upper bound on J.
López
Rosa
R
Teoría de la Materia Condensada, Instituto de Ciencia de Materiales de Madrid (CSIC) Cantoblanco, 28049 Madrid, Spain.
Aguado
Ramón
R
Platero
Gloria
G