ENERGY-LOSS FROM HOT-ELECTRONS IN A METAL-FILM

In this paper we discuss the energy-loss rate from electrons in a meta l film heated by an applied electric field. The acoustic-phonon spectr um in the film has been described by a confined three-dimensional phon on density of states that takes into account the finite thickness of t he film. The relationships between the energy-loss rate, the electric field, and the electron temperature are shown to depend on the acousti c coupling strength between the film and the underlying substrate. In agreement with previous analysis, with perfect acoustic coupling the e lectron temperature and electric field are related by a power law that depends on the phonon dimensionality. However, when the acoustic coup ling is less than perfect significant departures from the power-law re lationship are found.