Electronic and thermal sequential transport in metallic and superconducting two-junction arrays

TL;DR

This paper reviews sequential transport phenomena in metallic and superconducting two-junction arrays, providing numerical analysis of electrical and thermal transport properties in various device configurations based on the orthodox model.

Contribution

It offers a comprehensive self-consistent review with numerical calculations of I-V, G-V, and thermal transport in symmetric and asymmetric two-junction arrays, including effects of superconductivity and charging energy.

Findings

Identification of behavior at singularity-matching bias points

Dependence of microrefrigeration on charging energy

Impact of finite superconducting gap on Coulomb-blockade thermometry

Abstract

The description of transport phenomena in devices consisting of arrays of tunnel junctions, and the experimental confirmation of these predictions is one of the great successes of mesoscopic physics. The aim of this paper is to give a self-consistent review of sequential transport processes in such devices, based on the so-called "orthodox" model. We calculate numerically the current-voltage (I-V) curves, the conductance versus bias voltage (G-V) curves, and the associated thermal transport in symmetric and asymmetric two-junction arrays such as Coulomb-blockade thermometers (CBTs), superconducting-insulator-normal-insulator-superconducting (SINIS) structures, and superconducting single-electron transistors (SETs). We investigate the behavior of these systems at the singularity-matching bias points, the dependence of microrefrigeration effects on the charging energy of the island, and the effect of a finite superconducting gap on Coulomb-blockade thermometry.