Analysis of the Effect of Resonant Phonon Scattering on the Thermal Conductivity of CaF2

Abstract

An analysis is presented of the various phonon contributions to the thermal conductivity of CaF2 doped with 1·0% and 0·1 % of yttrium or thulium. The broad phonon resonant scattering term is found to reduce the low frequency phonon conduction significantly. This is responsible for the relatively stronger suppression of the conductivity at low temperatures in the phonon boundary scattering region. Thus broad quasilocalized phonon resonant scattering mechanisms have a similar effect to phonon precipitate scattering. It also follows that, in the case of a broad resonant scattering mechanism, a dip will not necessarily be seen in the conductivity.