Weak localization in monolayer and bilayer graphene

We demonstrate quantitative experimental evidence for a weak localization correction to the conductivity in monolayer and bilayer graphene systems. We show how inter- and intra-valley elastic scattering control the correction in small magnetic fields in a way which is unique to graphene. A clear difference in the forms of the correction is observed in the two systems, which shows the importance of the interplay between the elastic scattering mechanisms and how they can be distinguished. Our observation of the correction at zero-net carrier concentration in both systems is clear evidence of the inhomogeneity engendered into the graphene layers by disorder.