Paramagnons, weak disorder and positive giant magnetoresistance

Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801-3080, USA

Received: 11 November 1997
Accepted: 13 March 1998

Abstract

At low temperature and for finite spin scattering in a weakly disordered metal, for a certain value, predicted from our theory, of the material-dependent paramagnon interaction, the total conductivity becomes highly sensitive to the orbital effects of a finite magnetic field. As a consequence, positive giant magnetoresistance and giant corrections to the Hall coefficient arise. We obtain very good agreement between this theory and recent positive giant magnetoresistance experiments.