Regensburg 2022 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 21: Transport in Materials: Thermal transport
MM 21.2: Vortrag
Mittwoch, 7. September 2022, 10:30–10:45, H45
Searching and Finding Thermal Insulators via ab initio Green-Kubo Simulations — •Florian Knoop1,2, Thomas A.R. Purcell1, Matthias Scheffler1, and Christian Carbogno1 — 1The NOMAD Laboratory at the FHI-MPG and HU, Berlin, Germany — 2Department of Physics, Chemistry and Biology (IFM), Linköping University, Sweden
We present a first-principles search for thermal insulators in material space, covering hundreds of compounds in seven space groups, including simple rocksalt and zinc blende structures up to complex perovskites. Using the high-throughput framework FHI-vibes [1] and a recently developed measure for the strength of anharmonicity, [2] we identify 120 experimentally known materials with potential for ultra-low thermal conductivity <2 W/mK at room temperature, i.e., comparable to those of thermoelectrics such as SnSe. For the 60 most promising candidates, we perform non-perturbative, fully anharmonic ab initio Green-Kubo simulations [3] to include all anharmonic effects. Besides revealing seven ultra-insulating compounds, these calculations shed light on the importance of strong anharmonic effects not accessible in perturbative phonon formalisms, e.g., short-lived metastable configurations and precursors of phase transitions.
[1] F. Knoop et al., J. Open Source Softw. 5, 2671 (2020).
[2] F. Knoop et al., Phys. Rev. Mater. 4, 083809 (2020).
[3] C. Carbogno, R. Ramprasad, and M. Scheffler, Phys. Rev. Lett. 118, 175901 (2017).