Year: 2021
Type: article
Abstract: We investigate the microscopic mechanism of ultralow lattice thermal conductivity ( κ l ) of TlInTe 2 and its weak temperature dependence using a unified theory of lattice heat transport, that considers contributions arising from the particle-like propagation as well as wave-like tunneling of phonons. While we use the Peierls–Boltzmann transport equation (PBTE) to calculate the particle-like contributions ( κ l (PBTE)), we explicitly calculate the off-diagonal (OD) components of the heat-flux operator within a first-principles density functional theory framework to determine the contributions ( κ l (OD)) arising from the wave-like tunneling of phonons. At each temperature, T , we anharmonically renormalize the phonon frequencies using the self-consistent phonon theory including quartic anharmonicity, and utilize them to calculate κ l (PBTE) and κ l (OD). With the combined inclusion of κ l (PBTE), κ l (OD), and additional grain-boundary scatterings, our calculations successfully reproduce the experimental results. Our analysis shows that large quartic anharmonicity of TlInTe 2 (a) strongly hardens the low-energy phonon branches, (b) diminishes the three-phonon scattering processes at finite T, and (c) recovers the weaker than T −1 decay of the measured κ l .
Source: npj Computational Materials
Authors: Koushik Pal, Yi Xia, Chris Wolverton
Institution: Northwestern University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,890
Funders: National Science Foundation, U.S. Department of Energy, U.S. Department of Commerce, Northwestern University, Toyota Research Institute, National Energy Research Scientific Computing Center, National Institute of Standards and Technology, Office of Science, Basic Energy Sciences, Center for Hierarchical Materials Design
Awards: G1196738135, G122673668, G1286236842, G1286251239, G1314375578, G1414775356, G1445641779, G1676583131, G1677143136, G1816284028, G1863003419, DESIGN OF NEXT GENERATION THERMOELECTRICS, G2618837358, G3059599288, G30714459, G3083819904, G3226045097, G365575497, XSEDE 2.0: Integrating, Enabling and Enhancing National Cyberinfrastructure with Expanding Community Involvement, G3812616897, G419881185, G42916606, G4361631179, G4382344593, G4501827968, G498139845, G5076365615, G5296923526, G5590740066, DESIGN OF NEXT GENERATION THERMOELECTRICS, G5849692847, ADVANCED MATERIALS CENTER OF EXCELLENCE, G650090426, G6563589624, G6597714080, G6652958823, G6806689448, G805243471, G969889393
OpenAlex ID: W3112212465