Weak localization in monolayer and bilayer graphene

K. Kechedzhi; E. McCann; Vladimir I. Fal'ko; H. Suzuura; T. Ando; B. L. Altshuler

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arXiv · 0903.1848

Weak localization in monolayer and bilayer graphene

K. Kechedzhi·E. McCann·Vladimir I. Fal'ko·H. Suzuura·T. Ando·B. L. Altshuler

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Abstract

We describe the weak localization correction to conductivity in ultra-thin graphene films, taking into account disorder scattering and the influence of trigonal warping of the Fermi surface. A possible manifestation of the chiral nature of electrons in the localization properties is hampered by trigonal warping, resulting in a suppression of the weak anti-localization effect in monolayer graphene and of weak localization in bilayer graphene. Intervalley scattering due to atomically sharp scatterers in a realistic graphene sheet or by edges in a narrow wire tends to restore weak localization resulting in negative magnetoresistance in both materials.

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K. Kechedzhi, E. McCann, Vladimir I. Fal'ko, H. Suzuura, T. Ando, B. L. Altshuler. 2009-03-10. Weak localization in monolayer and bilayer graphene. https://arxiv.org/abs/0903.1848

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