Ballistic magnetotransport in graphene

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.