Thermal conductivity in PbTe from first principles

• Published in: Physical review. B, Condensed matter and materials physics Vol. 91; no. 21; p. 214310
• Main Authors: Romero, A. H., Gross, E. K. U., Verstraete, M. J., Hellman, Olle
• Format: Journal Article Web Resource
• Language: English
• Published: American Physical Society 29-06-2015
• Subjects: Condensed matter; Heat transfer; Intermetallics; Lead base alloys; Lead tellurides; Phonons; Physical, chemical, mathematical & earth Sciences; Physics; Physique; Physique, chimie, mathématiques & sciences de la terre; Thermal conductivity; Thermal properties
• ISSN: 1098-0121; 1550-235X; 1550-235X
• DOI: 10.1103/PhysRevB.91.214310

We Investigate the harmonic and enharmonic contributions to the phonon spectrum of lead telluride and perform a complete characterization of how thermal properties of PbTe evolve as temperature increases. We analyze the thermal resistivity's variation with temperature and clarify misconceptions about existing experimental literature. The resistivity initially increases sublinearly because of phase space effects and ultra strong anharmonic renormalizations of specific bands. This effect is the strongest factor in the favorable thermoelectric properties of PbTe, and it explains its limitations at higher T. This quantitative prediction opens the prospect of phonon phase space engineering to tailor the lifetimes of crucial heat carrying phonons by considering different structure or nanostructure geometries. We analyze the available scattering volume between TO and LA phonons as a function of temperature and correlate its changes to features in the thermal conductivity.