Magnetic structure of hydrogen-induced defects on graphene

Article

关键词: RENORMALIZATION-GROUP;    IMPURITIES;    TRANSPORT;    ANDERSON;    PHASE;   

DOI  :  10.1103/PhysRevB.85.115405

来源: SCIE

【 摘 要 】

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 halfway between the one corresponding to an adatom weakly coupled to pristine graphene and that of 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.

【 授权许可】

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