Nanoscale mechanisms for the reduction of heat transport in bismuth

Maxime Markov (1) , Jelena Sjakste (1) , Giorgia Fugallo (2) , Lorenzo Paulatto (3) , Michele Lazzeri (3) , Francesco Mauri (4) , Nathalie Vast (1)

1 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
2 IMPMC - Institut de minéralogie et de physique des milieux condensés
3 IMPMC - Institut de minéralogie, de physique des matériaux et de cosmochimie
4 Dipartimento di Fisica [Roma La Sapienza]

Hand-on routes to reduce lattice thermal conductivity (LTC) in bismuth have been explored by employing a combination of Boltzmann's transport equation and ab initio calculations of phonon-phonon interaction within the density functional perturbation theory. We have first obtained the temperature dependence of the bulk LTC in excellent agreement with available experiments. A very accurate microscopic description of heat transport has been achieved and the electronic contribution to thermal conductivity has been determined. By controlling the interplay between phonon-phonon interaction and phonon scattering by sample boundaries, we predict the effect of size reduction for various temperatures and nanostructure shapes. The largest heat transport reduction is obtained in polycrystals with grain sizes smaller than 100 nm.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Maxime Markov, Jelena Sjakste, Giorgia Fugallo, Lorenzo Paulatto, Michele Lazzeri, et al.. Nanoscale mechanisms for the reduction of heat transport in bismuth. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2016, ⟨10.1103/PhysRevB.93.064301⟩. ⟨hal-01284828⟩