© 2015 Elsevier B.V. Abstract We study the effects of a composition gradient and of a non-vanishing heat flux on the phase velocity of thermal waves along a graded system. We take into account non-local and non-linear effects by applying a generalized heat transport equation. We compare the results for high-frequency and low-frequency waves. For low frequency, we discuss the conditions in which thermal waves may propagate in Si<inf>x</inf>Ge<inf>1-x</inf> and (Bi<inf>1-x</inf>Sb<inf>x</inf>)<inf>2</inf>Te<inf>3</inf> systems. For high frequency, we discuss the influence of the relaxation of the flux of the heat flux on the heat wave propagation.
|Journal||Physica E: Low-Dimensional Systems and Nanostructures|
|Publication status||Published - 3 Jul 2015|
- Flux of heat flux
- Graded systems
- Phase speed
- Thermal waves