Giant Spin-Hall Effect Induced by the Zeeman Interaction in Graphene

Princeton Center for Theoretical Science and Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters (Impact Factor: 7.51). 08/2011; 107(9):096601. DOI: 10.1103/PhysRevLett.107.096601
Source: PubMed


We propose a new approach to generate and detect spin currents in graphene, based on a large spin-Hall response arising near the neutrality point in the presence of an external magnetic field. Spin currents result from the imbalance of the Hall resistivity for the spin-up and spin-down carriers induced by the Zeeman interaction, and do not involve a spin-orbit interaction. Large values of the spin-Hall response achievable in moderate magnetic fields produced by on-chip sources, and up to room temperature, make the effect viable for spintronics applications.

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