Energy loss from warm electrons in a thin alloy film

By using the technique of electron heating the authors have measured the energy loss lifetime from electron in thin Au 60 Pd 40 films over the temperature range 1-6K. They have analysed the results at lattice temperatures up to 3K and have shown them to be consistent with electron-acoustic-phonon scattering in the regime where the phonon wavelength is of the order of the elastic mean free path of the electron. The energy loss diffusion length obtained of l epsilon approximately=3.8 mu m is approximately 100 times greater than the film thickness suggesting a high degree of elastic scattering at the boundaries of the film.