Heat transport through atomic contacts

TL;DR

This paper reports the first measurements of heat transport through atomic gold contacts, demonstrating quantized thermal conductance and confirming the Wiedemann-Franz law at the atomic scale, advancing nanoscale heat manipulation.

Contribution

It introduces a novel experimental method to measure heat transfer in atomic junctions and verifies the proportionality between electrical and thermal conductance at the atomic level.

Findings

Thermal conductance of atomic gold contacts is quantized.

Electrical and thermal conductance are proportional, confirming the Wiedemann-Franz law.

First experimental verification of heat transport in atomic-scale contacts.

Abstract

Metallic atomic junctions pose the ultimate limit to the scaling of electrical contacts. They serve as model systems to probe electrical and thermal transport down to the atomic level as well as quantum effects occurring in one-dimensional systems. Charge transport in atomic junctions has been studied intensively in the last two decades. However, heat transport remains poorly characterized because of significant experimental challenges. Specifically the combination of high sensitivity to small heat fluxes and the formation of stable atomic contacts has been a major hurdle for the development of this field. Here we report on the realization of heat transfer measurements through atomic junctions and analyze the thermal conductance of single atomic gold contacts at room temperature. Simultaneous measurements of charge and heat transport reveal the proportionality of electrical and thermal conductance, quantized with the respective conductance quanta. This constitutes an atomic scale verification of the well-known Wiedemann-Franz law. We anticipate that our findings will be a major advance in enabling the investigation of heat transport properties in molecular junctions, with meaningful implications towards the manipulation of heat at the nanoscale