Revisiting thermal conductivity and interface conductance at the nanoscale

A simple and easy-to-handle semi-analytical model able to describe heat transport in heterostructures of length varying from the nano microscale is presented. It consists redefining three intrinsic parameters: ballistic thermal conductance, effective conductivity, interface conductance by using two temperatures T+ T? distinguishing phonon populations according direction their velocities instead standard pseudo-temperature T. The resulting agrees well with temperature profiles predicted advanced Monte Carlo simulation all regimes, i.e. diffusive, ballistic, quasi-ballistic even presence multiple interfaces. provide new insights into interpretation properties complex nanostructures.