Alfredo Fiorentino^1*, Paolo Pegolo^2*, Stefano Baroni^1,3*, Davide Donadio^4*

1 SISSA—Scuola Internazionale Superiore di Studi Avanzati, 34136 Trieste, Italy

2 Laboratory of Computational Science and Modeling, IMX, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland

3 CNR—Istituto Officina dei Materiali, SISSA, 34136 Trieste, Italy

4 Department of Chemistry, University of California, Davis, Davis, California 95616, United States

* Corresponding authors emails: afiorent@sissa.it, paolo.pegolo@epfl.ch, baroni@sissa.it, ddonadio@ucdavis.edu

DOI10.24435/materialscloud:az-f5 [version v1]

Publication date: Apr 15, 2025

How to cite this record

Alfredo Fiorentino, Paolo Pegolo, Stefano Baroni, Davide Donadio, Effects of colored disorder on the heat conductivity of SiGe alloys from first principles, Materials Cloud Archive 2025.59 (2025), https://doi.org/10.24435/materialscloud:az-f5

Description

Semiconducting alloys, in particular SiGe, have been employed for several decades as high- temperature thermoelectric materials. Devising strategies to reduce their thermal conductivity may provide a substantial improvement in their thermoelectric performance also at lower temper- atures. We have carried out an ab initio investigation of the thermal conductivity of SiGe alloys with random and spatially correlated compositional disorder employing the Quasi-Harmonic Green- Kubo (QHGK) theory with force constants computed from density functional theory. Leveraging QHGK and the hydrodynamic extrapolation to achieve size convergence, we obtained a detailed understanding of lattice heat conduction in SiGe and demonstrated that colored disorder suppresses thermal transport across the acoustic vibrational spectrum, leading to up to a 4-fold enhancement in the intrinsic thermoelectric figure of merit. This record contains input and analysis scripts to reproduce the findings of this article.

Materials Cloud sections using this data

Files

File name	Size	Description
README.md MD5md5:9262886a827649ccd561833296130a7c	2.2 KiB	Detailed description of the repository.
0_DFT.tar MD5md5:3a6e2e4a7523bc79db00999fea966eda	107.0 MiB	Folder containing inputs and examples for computing interatomic force constants from ab initio calculations.
1_crystal.tar MD5md5:46abe105d90114a30e2af62128855bd8	4.9 KiB	Folder with inputs for anharmonic and thermal conductivity calculations on the virtual crystals
2_disorder_alloy.tar MD5md5:c4c21230cea50ddf955fd8737e1d7f60	261.0 KiB	Folder containing inputs for generating and analyzing SiGe alloys with spatially (un)correlated disorder.
bw.tar MD5md5:49dc3d78e59e4365243129a9b17c8196	7.3 MiB	Folder containing precomputed interpolating functions (splines) for the inverse lifetimes of vibrational modes, accounting for various scattering sources.
plots.tar MD5md5:278789425715710e07f0f4a8ac346fbb	222.8 MiB	Folder containing the data and a Jupyter notebook to reproduce the figures from the reference.

License

Files and data are licensed under the terms of the following license: Creative Commons Attribution 4.0 International.
Metadata, except for email addresses, are licensed under the Creative Commons Attribution Share-Alike 4.0 International license.

External references

Keywords

Lattice thermal conductivity SiGe alloys Thermoelectric efficiency Disorder MaX