Nonlinear Propagation of Heat Pulses in Solids

Abstract

We have observed self-steepening and narrowing of transverse heat pulses in pure NaF at high input-pulse powers when the ambient temperature is in the ballistic regime of the thermal-conductivity curve. The details of such nonlinear propagation of heat are found to be in agreement with the theory proposed by Tappert and Varma, which shows that under certain conditions heat pulses develop an instability.