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arXiv · 0904.2396

Carrier Density and Magnetism in Graphene Zigzag Nanoribbons

J. Jung·A. H. MacDonald
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Abstract

The influence of carrier density on magnetism in a zigzag graphene nanoribbon is studied in a $π$-orbital Hubbard-model mean-field approximation. Departures from half-filling alter the magnetism, leading to states with charge density variation across the ribbon and parallel spin-alignment on opposite edges. Finite carrier densities cause the spin-density near the edges to decrease steadily, leading eventually to the absence of magnetism. At low doping densities the system shows a tendency to multiferroic order in which edge charges and spins are simultaneously polarized.

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J. Jung, A. H. MacDonald. 2009-06-25. Carrier Density and Magnetism in Graphene Zigzag Nanoribbons. https://doi.org/10.1103/physrevb.79.235433

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