Abstract
We report measurements of the thermal conductivity of high-quality crystals of the cubic semiconductors and . The thermal conductivity is temperature independent from 80 to 300 K at a value of approximately . Heat conduction is dominated by the lattice term, which we show is limited by umklapp and normal phonon-phonon scattering processes to a value that corresponds to the minimum possible, where the phonon mean free path equals the interatomic distance. Minimum thermal conductivity in cubic semiconductors is due to an extreme anharmonicity of the lattice vibrational spectrum that gives rise to a high Grüneisen parameter and strong phonon-phonon interactions. Members of this family of compounds are therefore most promising for thermoelectric applications, particularly as -type materials.
- Received 5 March 2008
DOI:https://doi.org/10.1103/PhysRevLett.101.035901
©2008 American Physical Society