Recently, Prof. Liu Dehuan’s research group (Prof. Yang Ronggui’s team) published a research paper entitled Effect of four-phonon interaction on phonon thermal conductivity and mean-free-path spectrum of high-temperature phase SnSe in a famous academic journal Applied Physics Letters. The paper was selected by the chief editor as an Editor’s Pick article, which was displayed on the homepage of the official website of Applied Physics Letters.
The paper’s authors are graduate students from the School of Energy and Power Engineering, HUST: Zhou Wenjiang, Daiyu, and Zhang Junjie. This work is supported by National Natural Science Foundation.
ABSTRACT
The phonon thermal conductivity and mean-free-path (MFP) spectrum of high-temperature phase SnSe (β-SnSe) are studied using the Boltzmann transport equation and ab initio approaches. The particle picture for phonon transport in β-SnSe is revisited, and the imaginary phonon frequencies caused by the ground-state within conventional density-functional theory are resolved. We show that between 800 and 950 K, the in-plane and cross-plane thermal conductivity has an average decrease of 38% and 19%, respectively, when four-phonon scatterings are considered. This large suppression of phonon transport stems mainly from the strong redistribution scattering process. With both the phonon and electron MFP spectra revealed, a characteristic length of 10 nm is suggested to reduce the in-plane and cross-plane thermal conductivity by 18% and 52%, respectively, via nanostructure engineering without sacrificing the power factor.
Paper Link: https://aip.scitation.org/doi/10.1063/5.0103919
