Kondo and Dicke effect in quantum-dots side coupled to a quantum wire

TL;DR

This paper investigates the Kondo and Dicke effects in a quantum-dot system coupled to a quantum wire, revealing interference phenomena and multiple Kondo regimes through a mean-field slave-boson approach.

Contribution

It introduces a theoretical analysis of the interplay between Kondo and Dicke effects in quantum-dot systems using a mean-field finite-U slave-boson formalism, highlighting quantum interference phenomena.

Findings

Transmission spectrum exhibits two anti-resonances at renormalized energies.

DOS shows two Kondo regimes with distinct Kondo temperatures.

Quantum interference explains the Dicke-like behavior in the system.

Abstract

Electron tunneling through quantum-dots side coupled to a quantum wire, in equilibrium and nonequilibrium Kondo regime, is studied. The mean-field finite-$U$ slave-boson formalism is used to obtain the solution of the problem. We have found that the transmission spectrum shows a structure with two anti-resonances localized at the renormalized energies of the quantum dots. The DOS of the system shows that when the Kondo correlations are dominant there are two Kondo regimes with its own Kondo temperature. The above behavior of the DOS can be explained by quantum interference in the transmission through the two different resonance states of the quantum dots coupled to common leads. This result is analogous to the Dicke effect in optics. We investigate the many body Kondo states as a function of the parameters of the system.