Thermal conductance of InAs nanowire composites

The ability to measure and understand heat flow in nanowire composites is crucial for applications ranging from high-speed electronics to thermoelectrics. Here we demonstrate the measurement of the thermal conductance of nanowire composites consisting of regular arrays of InAs nanowires embedded in PMMA using time-domain thermoreflectance (TDTR). On the basis of a proposed model for heat flow in the composite, we can, as a consistency check, extract the thermal conductivity Λ of the InAs nanowires and find Λ_NW = 5.3 ± 1.5 W m^-1 K^-1, in good agreement with theory and previous measurements of individual nanowires.