Thermodynamic uncertainty relation in atomic-scale quantum conductors

Abstract

The thermodynamic uncertainty relation (TUR), a trade-off relation between thermodynamic cost (entropy production) and precision (fluctuations), is expected to hold in nanoscale electronic conductors, when the electron transport process is quantum coherent and the transmission probability is constant (energy and voltage independent). We present measurements of the electron current and its noise in gold atomic-scale junctions and confirm the validity of the TUR for electron transport in realistic quantum coherent conductors. Furthermore, we show that it is beneficial to present the current and its noise as a TUR ratio to identify deviations from noninteracting-electron coherent dynamics.