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arXiv · 2110.03844

Ballistic magnetotransport in graphene

Ke Wang·T. A. Sedrakyan
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Abstract

We report that a perpendicular magnetic field introduces an anomalous interaction correction, $\delta \sigma$, to the static conductivity of doped graphene in the ballistic regime. The correction implies that the magnetoresistance, $\delta \rho_{xx}$ scales inversely with temperature $\delta \rho_{xx}(T) \propto 1/T$ in a parametrically large interval. When the disorder is scalar-like, the $\propto 1/T$ behavior is the leading contribution in the crossover between diffusive regime exhibiting weak localization and quantum magnetooscillations. The behavior originates from the field-induced breaking of the chiral symmetry of Dirac electrons around a single valley. The result is specific for generic two-dimensional Dirac materials which deviate from the half-filling. We conclude by proposing magnetotransport experiments, which have the capacity to detect the nature of impurities and defects in high-mobility Dirac monolayers such as recently fabricated ballistic graphene samples.

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Ke Wang, T. A. Sedrakyan. 2021-10-08. Ballistic magnetotransport in graphene. https://doi.org/10.1103/physrevb.105.l121114

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