Ballistic and diffusive transport of energy and heat in metals
نویسندگان
چکیده
We exploit a recently developed formalism to study the temporal behavior of the energy and heat transport in metals. This formalism shows the transition between ballistic and diffusive regimes and it highlights some interesting effects such as oscillations in the energy transport at very short-time scales. The energy relaxation of the conduction-band electrons in metals is considered to be governed by electron-phonon scattering, and the scattering time is taken to be averaged over the Fermi surface. The analysis separates the diffusive and the nondiffusive contributions to the heat transport. While the diffusive contribution shows an almost exponentially decaying behavior with time, the nondiffusive part shows a damped oscillating behavior. The origin of this oscillation will be discussed as well as the effect of the ambient temperature on the dynamics of the energy modes transport.
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