Coulomb blockade oscillations of conductance in the regime of strong tunneling

TL;DR

This paper analyzes the conductance oscillations in a quantum dot with nearly perfect contacts, revealing Coulomb blockade effects and Kondo physics at low temperatures.

Contribution

It provides an analytical calculation of conductance oscillations in the strong tunneling regime, highlighting the role of multi-channel Kondo physics.

Findings

Conductance oscillates with gate voltage due to Coulomb blockade.

Off-resonance conductance vanishes as T^2 at low temperatures.

Near resonance, physics is governed by a multi-channel Kondo fixed point.

Abstract

We study the transport through a quantum dot coupled to two leads by single-mode point contacts. The linear conductance is calculated analytically as a function of a gate voltage and temperature T in the case when transmission coefficients of the contacts are close to unity. As a function of the gate voltage, the conductance shows Coulomb blockade oscillations. At low temperatures, the off-resonance conductance vanishes as T^2, in agreement with the theory of inelastic co-tunneling. Near a resonance, the low-energy physics is governed by a multi-channel Kondo fixed point.