Hanbury-Brown-Twiss correlations and noise in the charge transfer statistics through a multiterminal Kondo dot

TL;DR

This paper investigates charge transfer statistics in a Kondo quantum dot with multiple terminals, revealing current anticorrelations related to HBT antibunching and correlations due to Kondo singlet polarization, useful for Fermi-liquid parameter extraction.

Contribution

It provides a detailed analysis of full counting statistics in the Kondo regime for multiterminal setups, highlighting novel anticorrelation effects and correlation mechanisms.

Findings

Anticorrelations of currents at the Kondo fixed point for N>2

Identification of correlations from Kondo singlet polarization

Weakening of effects away from the fixed point

Abstract

We analyze the full counting statistics of charge transfer through a quantum dot in the Kondo regime, when coupled to an arbitrary number of terminals N. At the unitary Kondo fixed point and for N>2 we recover distinct anticorrelations of currents in concurring transport channels, which are related to the fermionic Hanbury Brown and Twiss (HBT) antibunching. This effect weakens as one moves away from the fixed point. Furthermore, we identify a special class of current correlations that are due entirely to the virtual polarization of the Kondo singlet. These can be used for extracting information on the parameters of the underlying Fermi-liquid model.