Justin C. W. Song, Leonid S. Levitov
Massless Dirac fermions in graphene at charge neutrality form a strongly interacting system in which charge-neutral modes comprised of correlated particle-hole excitations play a dominant role. The neutral modes are essentially decoupled from charge dynamics in the absence of a magnetic field, but become strongly coupled to charge modes when a field is applied. We show that these ideas explain the recently observed giant magnetodrag, arising in classically weak fields when electron density in the layers is tuned near charge neutrality. We predict strong Hall drag in this regime, which is in stark departure from the weak coupling regime, where theory predicts the absence of Hall drag. Hall drag and magnetodrag arise in a wide temperature range and at classically weak magnetic fields, and feature an unusually strong dependence on field and carrier density.
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http://arxiv.org/abs/1303.3529
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