Related Experiment Video
Updated: Mar 7, 2026

Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
Study of radiative heat transfer in Ångström- and nanometre-sized gaps
Longji Cui1, Wonho Jeong1, Víctor Fernández-Hurtado2
1Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA.
Abstract:
Radiative heat transfer in Ångström- and nanometre-sized gaps is of great interest because of both its technological importance and open questions regarding the physics of energy transfer in this regime. Here we report studies of radiative heat transfer in few Å to 5 nm gap sizes, performed under ultrahigh vacuum conditions between a Au-coated probe featuring embedded nanoscale thermocouples and a heated planar Au substrate that were both subjected to various surface-cleaning procedures. By drawing on the apparent tunnelling barrier height as a signature of cleanliness, we found that upon systematically cleaning via a plasma or locally pushing the tip into the substrate by a few nanometres, the observed radiative conductances decreased from unexpectedly large values to extremely small ones-below the detection limit of our probe-as expected from our computational results. Our results show that it is possible to avoid the confounding effects of surface contamination and systematically study thermal radiation in Ångström- and nanometre-sized gaps.
Related Concept Videos
Mechanism of heat transfer
Absorption of Radiation
Mechanisms of Heat Transfer
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
Mechanisms of Heat Transfer I
Mechanisms of Heat Transfer II
Conduction, Convection and Radiation: Problem Solving
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...

