Fizika Nizkikh Temperatur: Volume 27, Number 9-10 (September 2001), p. 1159-1169 ( to contents , go back )
Search for the minimum thermal conductivity in mixed cryocrystals (CH4)1-x Krx
V. A. Konstantinov , V. G. Manzhelii, and V. P. Revyakin
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Lenin ave., Kharkov, 63103, Ukraine
R. O. Pohl
Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York, USA
Received March 21, 2001
The isochoric thermal conductivity of (CH4)1-x Krx solid solutions is studied between 40 K and ~ 150 K over the wide range of concentrations (x = 0.013, 0.032, 0.07, 0.115, 0.34, 0.71, 0.855, 0.937, and 0.97). A gradual transition from the thermal conductivity of a highly perfect crystal to the minimum thermal conductivity is observed as the crystal becomes increasingly more disordered. A qualitative description is given in the framework of Debye model of thermal conductivity, which takes into consideration the fact that phonon mean free path cannot decrease indefinitely.