Magnetic Phases of Graphene Nanoribbons under Potential Fluctuations

H. U. Özdemir, A. Altıntaş, A. D. Güçlü

Published 2015-11-16Version 1

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.