Non-diffusion theory of weak localization in graphene

TL;DR

This paper develops a non-diffusion theoretical framework for weak localization in graphene, explaining experimental magnetoresistance transitions and the effects of intervalley transitions on conductivity.

Contribution

It introduces a novel non-diffusion approach to weak localization in graphene, accounting for intervalley transitions and their impact on magnetoresistance.

Findings

Intervalley transitions cause a transition from weak antilocalization to localization.

The theory explains the non-monotonous magnetic field dependence of conductivity.

The model matches experimental observations across the entire weak magnetic field range.

Abstract

We put forward a theory of the weak localization in two dimensional graphene layers which explains experimentally observable transition between positive and negative magnetoresistance. Calculations are performed for the whole range of classically weak magnetic field with account on intervalley transitions. Contribution to the quantum correction which stems from closed trajectories with few scatterers is carefully taken into account. We show that intervalley transitions lead not only to the transition from weak antilocalization to the weak localization, but also to the non-monotonous dependence of the conductivity on the magnetic field.