Positive Magneto-Resistance in Quasi-1D Conductors

TL;DR

This paper introduces a simple model explaining positive magnetoresistance in quasi-1D conductors, capturing high and low temperature transport behaviors and the effects of spin-flip scattering, with quantitative agreement to experimental data.

Contribution

The paper presents a new qualitative model that unifies high and low temperature transport regimes in quasi-1D conductors, explaining positive magnetoresistance through spin-flip scattering effects.

Findings

Model agrees quantitatively with $TTT_2I_{3-eta}$ data.

Positive magnetoresistance explained by spin-flip scattering.

Crossover temperature determined by elastic and inelastic scattering times.

Abstract

We present here a simple qualitative model that interpolates between the high and low temperature properties of quasi-1D conductors. At high temperatures we argue that transport is governed by inelastic scattering whereas at low temperatures the conductance decays exponentially with the electron dephasing length. The crossover between these regimes occurs at the temperature at which the elastic and inelastic scattering times become equal. This model is shown to be in quantitative agreement with the organic conductor $TTT_2I_{3-\delta}$. Within this model, we also show that on the insulating side, the positive magnetoresistance of the form $(H/T)^2$ observed in $TTT_2I_{3-\delta}$ and other quasi-1D conductors can be explained by the role spin-flip scattering plays in the electron dephasing rate.