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In this report we investigate the Kapitza resistance RK at an interface between a classical solid and a 4He quantum crystal, as a function of temperature. We provide a premise for RK based on a combination of two separate mechanisms which occur simultaneously. Owing to the fact that the phonon wavelengths in solid 4He and in the superfluid are of the same order of magnitude, we infer that one mechanism is due to resonant scattering of phonons by nanoscale surface roughness as predicted by Adamenko and Fuks1 for solid/superfluid interfaces. The other mechanism involves the interaction of thermal phonons with mobile vibrating dislocations within solid 4He. The present analysis demonstrates the plausibility of these two mechanisms in solving the long outstanding problem of the Kapitza resistance anomaly of solid 4He in contact with copper for temperatures ranging from 0.4 to 2 K.

In a recent paper, it is shown that the thermal boundary Kapitza resistance between a solid and superfluid helium is explained by resonant scattering of phonons from surface roughness heights, as described in the Adamenko and Fuks (AF) model. We reexamine the original experiments of thermal transfer between a solid (platinum and copper) and superfluid helium conducted by P.L. Kapitza in 1940. In particular, we analyze his experimental results for the different surface treatments of the solid in light of the AF model. Time scales for diffuse scattering of phonons at the interface are estimated. Also the role of a layer of varnish on a copper surface is reinterpreted.

Kapitza resistance measurements conducted at T > 1 K on silicon and niobium single crystals in contact with helium demonstrate respectively the importance of atomic scale surface roughness and dislocations due to surface damage at the boundary. Two different experimental configurations were used.