Influence of trigonal warping on interference effects in bilayer graphene

TL;DR

This paper investigates how trigonal warping affects interference effects in bilayer graphene, revealing that weak localization depends on intervalley scattering and analyzing the resulting magnetoresistance.

Contribution

It demonstrates the conditions under which weak localization occurs in bilayer graphene and evaluates the impact of trigonal warping on interference effects.

Findings

Weak localization in bilayer graphene requires strong intervalley scattering.

Trigonal warping suppresses weak localization effects.

Magnetoresistance is influenced by the degree of intervalley scattering.

Abstract

Bilayer graphene (two coupled graphitic monolayers arranged according to Bernal stacking) is a two-dimensional gapless semiconductor with a peculiar electronic spectrum different from the Dirac spectrum in the monolayer material. In particular, the electronic Fermi line in each of its valleys has a strong p -> -p asymmetry due to a trigonal warping, which suppresses the weak localization effect. We show that weak localisation in bilayer graphene may be present only in devices with pronounced intervalley scattering, and we evaluate the corresponding magnetoresistance.