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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    • "The latter occurs only when streamlines run into system boundary, contacts, or some other inhomogeneity, as in Fig.1. Recently , nonlocal electrical response mediated by chargeless modes was shown to be uniquely sensitive to the quantities which are not directly accessible in electrical transport measurements, in particular spin currents and valley currents.[18] [19] [20] In a similar manner, the nonlocal response discussed here gives a diagnostic of viscous transport which is more direct and powerful than any FIG. "
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