Effect of the boundary condition on the Kapitza resistance between superfluid He3−B and sintered metal

Understanding the temperature dependence of thermal boundary resistance, or Kapitza resistance, between liquid helium and sintered metal has posed a problem in low-temperature physics for decades. In the ballistic regime of superfluid ^{3}\mathrm{He}\text{\ensuremath{-}}B we find the Kapitza resistance can be described via scattering of thermal excitations (quasiparticles) with a macroscopic geometric area, rather than the sintered metal's...