Abstract
The anharmonic interaction (third-order elastic Hamiltonian) between fractons (short-length-scale vibrational excitations) and phonons (long-length-scale vibrational excitations) is introduced. The relationship between phonon-fracton scattering rates and the thermal conductivity is developed. Two relevant anharmonic lifetimes are calculated: two phonons combining into a single fracton, and one phonon combining with a fracton to produce a fracton. The former is important to the behavior of in the plateau regime; the latter to at temperatures above the plateau regime. The latter is interpreted in terms of phonon-assisted fracton hopping, and gives rise to an extra heat conductance which increases linearly in the temperature T. This behavior appears to be in agreement with recent high-temperature measurements of in epoxy resin by de Oliveira and Rosenberg.
Original language | English |
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Pages (from-to) | 2726-2734 |
Number of pages | 9 |
Journal | Physical Review B |
Volume | 34 |
Issue number | 4 |
DOIs | |
State | Published - 1 Jan 1986 |
Externally published | Yes |
ASJC Scopus subject areas
- Condensed Matter Physics