Weak localisation in bilayer graphene

TL;DR

This paper reports the first experimental study of quantum interference effects in bilayer graphene, revealing unique weak localisation behavior influenced by elastic scattering processes.

Contribution

It provides new insights into weak localisation in bilayer graphene, highlighting the roles of dephasing and elastic scattering in quantum interference corrections.

Findings

Negative magnetoresistance observed at various carrier densities

Weak localisation behavior differs from conventional 2D systems

Elastic processes affect time-reversal symmetry and intervalley scattering

Abstract

We have performed the first experimental investigation of quantum interference corrections to the conductivity of a bilayer graphene structure. A negative magnetoresistance - a signature of weak localisation - is observed at different carrier densities, including the electro-neutrality region. It is very different, however, from the weak localisation in conventional two-dimensional systems. We show that it is controlled not only by the dephasing time, but also by different elastic processes that break the effective time-reversal symmetry and provide invervalley scattering.