Thermal conductivity of systems with a gap in the phonon spectrum*

Project supported by the Ural Branch of the Russian Academy of Sciences, Russia (Grant No. 18-2-2-12), the Russian Foundation for Basic Research, Russia (Grant Nos. 16-07-00529 and 18-07-00191), and the Financing Program, Russia (Grant No. AAAA-A16-116021010082-8).

Salamatov E
       

(color online) Phonon diffusion coefficient D(x) calculated at different values parameters of (1) xr = 0.5 and cv = 0.5, (2) xr = 0.5 and cv = 0.2, (3) xr = 1.0 and cv = 0.5, and (4) xr = 1.0 and cv = 0.2. The dashed curve corresponds to the case of absolutely hard spheres.