Time-resolved thermoreflectivity of thin gold films and its dependence on the ambient temperature

Abstract
The dependence on the ambient temperature of the transient thermoreflectivity of single-crystal thin gold films has been determined experimentally. We assume the existence of an effective electron temperature throughout the experiment, and demonstrate that it is possible to transform the temporal evolution of the thermoreflectivity to the temporal evolution of the effective electron temperature, and to determine the dependence of the decay of the effective electron temperature on the ambient temperature.