Fast thermometry with a proximity Josephson junction

TL;DR

This paper demonstrates a fast, minimally invasive thermometer based on a proximity Josephson junction that can measure electron temperatures in mesoscopic systems under steady and nonequilibrium conditions, enabling advanced thermal studies.

Contribution

It introduces a novel method for rapid, low-back-action electron temperature measurement using a proximity Josephson junction, suitable for mesoscopic thermal transport and calorimetry.

Findings

Successful real-time monitoring of electron temperature in nonequilibrium

Minimal back-action due to zero additional dissipation or thermal conductance

Potential for studying thermal transport in mesoscopic systems

Abstract

We couple a proximity Josephson junction to a Joule-heated normal metal film and measure its electron temperature under steady state and nonequilibrium conditions. With a timed sequence of heating and temperature probing pulses, we are able to monitor its electron temperature in nonequilibrium with effectively zero back-action from the temperature measurement in the form of additional dissipation or thermal conductance. The experiments demonstrate the possibility of using a fast proximity Josephson junction thermometer for studying thermal transport in mesoscopic systems and for calorimetry.