HEAT-TRANSFER IN IMPURE CRYOCRYSTALS - RESONANCE IMPURITY SCATTERING AND 3-PHONON PROCESSES

A theoretical model of heat transfer is proposed for cryocrystals with heavy impurities lacking intrinsic degrees of freedom. The theory is based on successive solution of the kinetic equation for phonon gas. T he high excess impurity thermal resistivity and its nonlinear dependen ce on point defect concentration are resulted from the interference be tween normal processes and resonance scattering by impurity quasi-loca l levels. A microscopic estimation of the parameters involved in the t heory is presented. The calculated results provide interpretation of e xperimental data on heat conductivity of solid para-hydrogen with rare -gas impurities.