Thermal conductivity of high purity synthetic single crystal diamonds
Abstract
Thermal conductivity of three high purity synthetic single crystalline diamonds has been measured with high accuracy at temperatures from 6 to 410 K. The crystals grown by chemical vapor deposition and by high-pressure high-temperature technique demonstrate almost identical temperature dependencies κ (T ) and high values of thermal conductivity, up to 24 W cm-1K-1 at room temperature. At conductivity maximum near 63 K, the magnitude of thermal conductivity reaches 285 W cm-1K-1 , the highest value ever measured for diamonds with the natural carbon isotope composition. Experimental data were fitted with the classical Callaway model for the lattice thermal conductivity. A set of expressions for the anharmonic phonon scattering processes (normal and umklapp) has been proposed which gives an excellent fit to the experimental κ (T ) data over almost the whole temperature range explored. The model provides the strong isotope effect, nearly 45%, and the high thermal conductivity (>24 W cm-1K-1 ) for the defect-free diamond with the natural isotopic abundance at room temperature.
- Publication:
-
Physical Review B
- Pub Date:
- April 2018
- DOI:
- 10.1103/PhysRevB.97.144305
- Bibcode:
- 2018PhRvB..97n4305I