Work

Thermal conductivities of amorphous SiO2 films by approach-to-equilibrium molecular dynamics

Year: 2026

Type: article

Abstract: The thermal conductivity of stand-alone amorphous SiO$_2$ films is calculated both in and cross plane. In both cases, the approach-to-equilibrium molecular dynamics (AEMD) method is employed, showing how the method can be extended to calculate the cross-plane thermal conductivity. The study is conducted within the first-principles molecular dynamics framework. We ascertain that the thermal conductivity in the plane remains unaffected by the presence of free surfaces. Remarkably, even for a thickness of 2 nm, the thermal conductivity is found to be equal to (1.3$\pm$0.1) W K$^{-1}$ m$^{-1}$, which is in accordance with the measured macroscopic value. With regard to cross-plane thermal conductivity, the value for a film with thickness $d$ is equivalent to that obtained by AEMD in the case of a bulk with a periodicity of $2d$. The cross-plane thermal conductivity is shown to decrease for thicknesses below 3 nm.

Source: Solid State Sciences

DOI: 10.1016/j.solidstatesciences.2026.108262

Authors: Louis Petit, Cheick O. Diarra, Achille Lambrecht, Ibrahim Bel-Hadj, Mauro Boero, Evelyne Martin

Institutions: Centre National de la Recherche Scientifique, Laboratoire des Sciences de l'Ingénieur, de l'Informatique et de l'Imagerie, Université de Strasbourg

Language: English

Topic: Thermal properties of materials

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,070

Funders: Equipex, Agence Nationale de la Recherche, Université de Strasbourg, Grand Équipement National De Calcul Intensif