Affiliation
Lancaster University
Title
Giant magnetoresistance of Dirac plasma in monolayer graphene
Abstract
The Dirac electron-hole plasma in monolayer graphene demonstrates a remarkable parabolic magnetoresistivity that exceeds 100% at 0.1 T, even at room temperature. This behavior, which is orders of magnitude stronger than that in any other known system, can be attributed to graphene's massless Dirac spectrum and ultra-high carrier mobility. Notably, this high mobility persists in Dirac plasma at room temperature, despite the extremely frequent Planckian limit scattering determined by the uncertainty principle.
With the onset of Landau quantization at higher magnetic fields, a unique linear magnetoresistivity emerges. This feature is predominantly temperature-independent and can be suppressed by proximity screening, which suggests a many-body origin. We interpret this linear behavior as cyclotron orbit diffusion on the zeroth Landau level, mediated by a network of shallow electron-hole puddles.
To underscore the uniqueness of the magnetoresistance of the Dirac plasma at the charge neutrality point in monolayer graphene, we contrast it with the magnetoresistance of graphite and bilayer graphene. These systems exhibit lower mobility due to the finite mass of their charge carriers.