Thermal contact resistance between two nanoparticles

TL;DR

This paper calculates the thermal conductance between two nanoparticles using Molecular Dynamics, revealing it depends on atomic interactions and matches theoretical predictions, with conductance around 1 microWatt per Kelvin for nanoscale contacts.

Contribution

It introduces a method to compute nanoparticle contact conductance based on fluctuation-dissipation theorem and atomic interactions, providing quantitative estimates for silica nanoparticles.

Findings

Conductance is proportional to the number of atoms involved.

Atomic contribution to conductance ranges from 0.5 to 3 nW/K.

Contact conductance is approximately 1 μW/K for 1-10 nm² contact areas.

Abstract

We compute the thermal conductance between two nanoparticles in contact based on the Molecular Dynamics technique. The contact is generated by letting both particles stick together under van der Waals attractions. The thermal conductance is derived from the fluctuation-dissipation theorem and the time fluctuations of the exchanged power. We show that the conductance is proportional to the atoms involved in the thermal interaction. In the case of silica, the atomic contribution to the thermal conductance is in the range of 0.5 to 3 nW.K-1. This result fits to theoretical predictions based on characteristic times of the temperature fluctuation. The order of magnitude of the contact conductance is 1 \mu W.K-1 when the cross section ranges from 1 to 10nm2.