Glass-like behaviour of thermal conductivity of - solid solutionsP. Stachowiak1, E. Pisarska1, A. Jezowski1 and A. I. Krivchikov2
1 Institute for Low Temperatures and Structure Research, Polish Academy of Sciences PN 1410, 50-950 Wroclaw, Poland
2 Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine - 47 Lenin Ave., Kharkov 61103, Ukraine
received 12 December 2005; accepted in final form 9 February 2006
published online 1 March 2006
Some mixed crystals show a low-temperature thermal-conductivity dependence on temperature similar to that of amorphous solids. This phenomenon is usually ascribed to a disorder of another kind. In the current paper we report results of measurements of the thermal conductivity of - solid solution which also displays a glass-like behaviour for some concentrations of deuterated methane. Here, however, the disorder appearing at these concentrations of cannot account for the characteristic plateau. Instead, we explain it in terms of an enhancement of the phonon-rotation interaction resulting from lowering the symmetry of the molecular field.
66.70.+f - Nonelectronic thermal conduction and heat-pulse propagation in solids; thermal waves.
63.20.Mt - Phonon-defect interactions.
© EDP Sciences 2006