Manifestation of the Lower Limit to Thermal Conductivity in the Solidified Inert Gases

Abstract

The deviations of the isochoric thermal conductivity of the solidified inert gases Ar, Kr, and Xe from the law Λ∝1/T have been analyzed within the framework of the simple Debye model of thermal conductivity taking into account that the phonon mean-free path cannot decrease indefinitely. It has been shown that the best agreement with experiment is observed by assuming that the minimum of the phonon mean-free path is of the order of the interatomic distance. This supports the picture of localized exitations at highest frequencies that hop from site to site.