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arXiv · 1112.2529

Magnetic Structure of Hydrogen Induced Defects on Graphene

J. O. Sofo·Gonzalo Usaj·P. S. Cornaglia·A. M. Suarez·A. D. Hernández-Nieves·C. A. Balseiro
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Abstract

Using density functional theory (DFT), Hartree-Fock, exact diagonalization, and numerical renormalization group methods we study the electronic structure of diluted hydrogen atoms chemisorbed on graphene. A comparison between DFT and Hartree-Fock calculations allows us to identify the main characteristics of the magnetic structure of the defect. We use this information to formulate an Anderson-Hubbard model that captures the main physical ingredients of the system, while still allowing a rigorous treatment of the electronic correlations. We find that the large hydrogen-carbon hybridization puts the structure of the defect half-way between the one corresponding to an adatom weakly coupled to pristine graphene and a carbon vacancy. The impurity's magnetic moment leaks into the graphene layer where the electronic correlations on the C atoms play an important role in stabilizing the magnetic solution. Finally, we discuss the implications for the Kondo effect.

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J. O. Sofo, Gonzalo Usaj, P. S. Cornaglia, A. M. Suarez, A. D. Hernández-Nieves, C. A. Balseiro. 2011-12-12. Magnetic Structure of Hydrogen Induced Defects on Graphene. https://doi.org/10.1103/physrevb.85.115405

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