SMALL-Q ELECTRON-PHONON SCATTERING AND LINEAR DC RESISTIVITY IN HIGH-T-C OXIDES

We examine the effect on the de resistivity of small-q electron-phonon scattering, in a system with the electronic topology of the high-T-c oxides. Despite the fact that the scattering is dominantly forward, it s contribution to the transport can be significant due to ''undulation s'' of the bands in the flat region and to the umpklapp process. When the extended van Hove singularities are sufficiently close to E-F, the acoustic branch of: the phonons contribute significantly to the trans port. In that case one can obtain linear T-dependent resistivity down to temperatures as low as 10 K, even if electrons are scattered also b y optical phonons of about 500 It as reported by Raman measurements.