Magnetoresistance in quasi-one-dimensional metals due to Fermi surface cold spots

Abstract

In a number of quasi-one-dimensional organic metals the dependence of the magnetoresistance on the direction of the magnetic field is quite different from the predictions of Boltzmann transport theory for a Fermi liquid with a scattering rate that is independent of momentum. We consider a model in which there are large variations in the scattering rate over the Fermi surface. The model is the quasi-one-dimensional version of the ``cold spots'' model introduced by Ioffe and Millis to explain anomalous transport properties of the metallic phase of the cuprate superconductors. The dependence of the resistance, in the most and least conducting directions, on the direction and magnitude of the magnetic field are calculated. The calculated magnetoresistance has a number of properties that are quite distinct from conventional transport theory such as magic angle effects a significant magnetoresistance when the field and current are both in the least conducting direction. However, the model cannot give a complete description of the unusual properties of (TMTSF)2PF6 at pressures of 8-11 kbar.