Unified description of phase lapses, population inversion, and correlation-induced resonances in double quantum dots

Vyacheslavs Kashcheyevs*, Avraham Schiller, Amnon Aharony, Ora Entin-Wohlman

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

68 Scopus citations

Abstract

The two-level model for a double quantum dot coupled to two leads of spinless electrons, which is ubiquitously used to describe charge oscillations, transmission-phase lapses and correlation-induced resonances, is considered in its general form. The model features arbitrary tunnelling matrix elements among the two levels and the leads and between the levels themselves (including the effect of Aharonov-Bohm fluxes), as well as interlevel repulsive interactions. We show that this model is exactly mapped onto a generalized Anderson model of a single dot, where the electrons acquire a pseudospin degree of freedom that is conserved by the tunnelling but not within the dot. Focusing on the local-moment regime where the dot is singly occupied, we show that the effective low-energy Hamiltonian is that of the anisotropic Kondo model in the presence of a tilted magnetic field. For moderate values of the (renormalized) field, the Bethe ansatz solution of the isotropic Kondo model allows us to derive accurate expressions for the dot occupation numbers, and henceforth its zero-temperature transmission. Our results are in excellent agreement with those obtained from the Bethe ansatz for the isotropic Anderson model, and with the functional and numerical renormalization-group calculations of Meden and Marquardt [Phys. Rev. Lett. 96, 146801 (2006)], which are valid for the general anisotropic case. In addition we present highly accurate estimates for the validity of the Schrieffer-Wolff transformation (which maps the Anderson Hamiltonian onto the low-energy Kondo model) at both the high- and low-magnetic field limits. Perhaps most importantly, we provide a single coherent picture for the host of phenomena to which this model has been applied.

Original languageEnglish
Article number115313
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume75
Issue number11
DOIs
StatePublished - 12 Mar 2007
Externally publishedYes

Fingerprint

Dive into the research topics of 'Unified description of phase lapses, population inversion, and correlation-induced resonances in double quantum dots'. Together they form a unique fingerprint.

Cite this