We introduce a new model of a sintered metallic powder in which neighbouring grains are either fused together with probability P or weakly coupled with probability (1-P). A new selective renormalization technique is used to compute the density of vibrational states ρ(ω) at wavelengths λ greater than or of order a typical grain size L. For λ≫L, ρ(ω) is Debye-like, whereas for λ>L, a cross over to fracton-like behaviour is observed, consistent with recent experimental results. BCS theory is employed to yield an expression for the heat transfer Q between sinter modes and 3He-B quasi-particles. This expression is combined with ρ(ω) to yield for the first time a fully microscopic evaluation of the temperature dependence of \dotQ.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.