Influence of device non-uniformities on the accuracy of Coulomb blockade thermometry

TL;DR

This paper analyzes how non-uniformities in tunnel junction arrays affect the accuracy of Coulomb blockade thermometry, providing analytical and numerical insights into temperature errors and fabrication implications.

Contribution

It offers a new understanding of the impact of device non-uniformities on Coulomb blockade thermometry accuracy, extending analysis beyond high-temperature regimes.

Findings

Temperature errors are proportional to junction resistance variance.

Analytical and numerical results support the proportionality relationship.

Implications for fabrication uniformity are discussed.

Abstract

We investigate temperature errors of Coulomb blockade thermometer (CBT) arising from inevitable non-uniformities in tunnel junction arrays. The errors are proportional to the junction resistance variance in the universal operation regime and this result holds approximately also beyond this originally studied high temperature range. We present both analytical and numerical results, and discuss briefly their implications on achievable uniformity based on state-of-the-art fabrication of sensors.