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arXiv · 1511.05034

Magnetic Phases of Graphene Nanoribbons under Potential Fluctuations

H. U. Özdemir·A. Altıntaş·A. D. Güçlü
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Abstract

We investigate the effects of long-range potential fluctuations and electron-electron interactions on electronic and magnetic properties of graphene nanoribbons with zigzag edges using an extended mean-field Hubbard model. We show that electron-electron interactions make the edge states robust against potential fluctuations. When the disorder is strong enough, the presence of electron-hole puddles induces a magnetic phase transition from antiferromagnetically coupled edge states to ferromagnetic coupling, in agreement with recent experimental results.

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H. U. Özdemir, A. Altıntaş, A. D. Güçlü. 2016-01-18. Magnetic Phases of Graphene Nanoribbons under Potential Fluctuations. https://doi.org/10.1103/physrevb.93.014415

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