Mesoscopic Kondo effect of a quantum dot embedded in an Aharonov-Bohm ring with intradot spin-flip scattering

TL;DR

This paper investigates how intradot spin-flip scattering affects the mesoscopic Kondo effect in a quantum dot within an Aharonov-Bohm ring, revealing peak splitting, current suppression, and parity-dependent phenomena.

Contribution

It introduces a finite-U slave-boson mean-field approach to analyze the impact of spin-flip scattering on Kondo physics in mesoscopic rings, highlighting novel effects on persistent current behavior.

Findings

Kondo peak splits into two peaks due to spin-flip scattering.

Persistent current is suppressed and adopts a sine form with increasing R.

Reverse current direction occurs for odd parity with spin-flip scattering.

Abstract

We study the Kondo effect in a quantum dot embedded in a mesoscopic ring taking into account intradot spin-flip scattering $R$. Based on the finite-$U$ slave-boson mean-field approach, we find that the Kondo peak in the density of states is split into two peaks by this coherent spin-flip transition, which is responsible for some interesting features of the Kondo-assisted persistent current circulating the ring: (1) strong suppression and crossover to a sine function form with increasing $R$; (2) appearance of a "hump" in the $R$-dependent behavior for odd parity. $R$-induced reverse of the persistent current direction is also observed for odd parity.