Role of electron-phonon coupling in thermal conductance of metal-nonmetal interfaces
Abstract
We theoretically show that the thermal conductance associated with electron-phonon coupling in a metal near a metal-nonmetal interface can be estimated as hep=√Gkp , where G is the volumetric electron-phonon coupling constant and kp is the phonon or lattice thermal conductivity of the metal. The expression suggests hep≈1/√T at temperatures comparable to the Debye temperature of the metal. The predicted values of hep fall within the range of conductance values experimentally observed (0.3-1 GW/m2 K), suggesting that it cannot be ignored, and could even play a dominant role at high temperatures. Predictions of the total thermal conductance, that include both electron-phonon and phonon-phonon interfacial conductances, show reasonable agreement in its temperature dependence with experimental data for TiN/MgO interfaces.
- Publication:
-
Applied Physics Letters
- Pub Date:
- June 2004
- DOI:
- 10.1063/1.1758301
- Bibcode:
- 2004ApPhL..84.4768M
- Keywords:
-
- 63.20.Kr;
- 72.15.Eb;
- 66.70.+f;
- 68.35.Ja;
- Phonon-electron and phonon-phonon interactions;
- Electrical and thermal conduction in crystalline metals and alloys;
- Nonelectronic thermal conduction and heat-pulse propagation in solids;
- thermal waves;
- Surface and interface dynamics and vibrations