Singularity-matching peaks in superconducting single-electron transistor

TL;DR

This paper reports the experimental observation of singularity-matching peaks in the I-V characteristics of a superconducting single-electron transistor, caused by quasiparticle density of states matching influenced by Coulomb blockade at higher temperatures.

Contribution

First experimental demonstration of singularity-matching peaks in superconducting single-electron transistors at elevated temperatures.

Findings

Observed peaks on I-V curve matching quasiparticle density of states

Peaks caused by Coulomb blockade energy shift

Validates theoretical predictions of singularity matching

Abstract

We report the experimental observation of the recently predicted peaks on the I-V curve of the superconducting single-electron transistor at relatively high temperatures. The peaks are due to the matching of singularities in the quasiparticle density of states in two electrodes of a tunnel junction. The energy shift due to Coulomb blockade provides the matching at finite voltage.