Thermal conductance of strongly bonded metal-oxide interfaces

We report the results of time-domain thermoreflectance (TDTR) measurements of two strongly bonded metal-oxide systems with unusually large thermal conductances. We find that TDTR data for the epitaxial SrRuO3/SrTiO3 interface is consistent with an interface conductance G > 0.8 GW m(-2) K-1. For an Al/MgO interface at a pressure of 60 GPa, we find G approximate to 1.1 GW m(-2) K-1. Both are within 40% of the maximum possible conductance for these systems, as predicted by simple theory.