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arXiv · 1301.5024

Gate-Tunable Exchange Coupling Between Cobalt Clusters on Graphene

Hua Chen·Qian Niu·Zhenyu Zhang·Allan H. MacDonald
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Abstract

We use spin-density-functional theory (SDFT) ab initio calculations to theoretically explore the possibility of achieving useful gate control over exchange coupling between cobalt clusters placed on a graphene sheet. By applying an electric field across supercells we demonstrate that the exchange interaction is strongly dependent on gate voltage, but find that it is also sensitive to the relative sublattice registration of the cobalt clusters. We use our results to discuss strategies for achieving strong and reproducible magneto-electric effects in graphene/transition-metal hybrid systems.

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Hua Chen, Qian Niu, Zhenyu Zhang, Allan H. MacDonald. 2013-01-21. Gate-Tunable Exchange Coupling Between Cobalt Clusters on Graphene. https://doi.org/10.1103/physrevb.87.144410

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