ELECTRIC-FIELD HEATING OF SUPPORTED AND FREESTANDING AUPD FINE WIRES

The electrical properties of supported and free-standing AuPd wires of dimensions 8 mu m multiplied by 50 multiplied by 30 nm have been studied. The low temperature resistance rise observed for the supported wire is described in terms of one dimensional Coulomb interactions with a screening parameter F approximately equals one-half . The resistance rise of the free standing wire, however, shows a more two dimensional behavior. In both cases the resistance change as a function of temperature has been used as a thermometer to measure the electron temperature in the study of energy loss from an electron system heated by an electric field. It is found that for a supported wire the energy loss is limited by the electron-phonon scattering rate which is proportional to the square of the electron temperature. For a free standing wire the heat loss is limited by the diffusion of electrons and phonons along the wire.