Impurity scattering and frequency-dependent conductivity in spin density waves

¹ Department of Physics, Technical University of Budapest - H-1521 Budapest, Hungary
² Research Institute for Solid State Physics and Optics P.O. Box 49, H-1525 Budapest, Hungary
³ Department of Physics and Astronomy, University of Southern California Los Angeles, CA 90089-0484, USA

Received: 25 February 1999
Accepted: 31 May 1999

Abstract

The quasiparticle contribution to the frequency-dependent electric conductivity in the presence of randomly distributed impurities is calculated within mean-field theory for spin density waves as formed in quasi–one-dimensional conductors like Bechgaard salts. Interchain hopping is taken into account and the effects of imperfect nesting are considered. In case of an electric field perpendicular to the chain direction there is no collective contribution to the conductivity and our results are directly applicable to recent measurements on both and quenched . The experimental data are well described by the theory in its clean limit, with somewhat larger scattering in the salt.