### Résumé

langue originale | Anglais |
---|---|

Numéro d'article | 045448 |

Nombre de pages | 10 |

journal | Phys. Rev. B |

Volume | 86 |

Numéro de publication | 4 |

Les DOIs | |

état | Publié - 27 juil. 2012 |

### Empreinte digitale

### Citer ceci

*Phys. Rev. B*,

*86*(4), [045448]. https://doi.org/10.1103/PhysRevB.86.045448

}

*Phys. Rev. B*, VOL. 86, Numéro 4, 045448. https://doi.org/10.1103/PhysRevB.86.045448

**Long-range interactions between substitutional nitrogen dopants in graphene: Electronic properties calculations.** / Lambin, Philippe; Amara, Hakim; Ducastelle, Francois; Henrard, L.

Résultats de recherche: Contribution à un journal/une revue › Article

TY - JOUR

T1 - Long-range interactions between substitutional nitrogen dopants in graphene: Electronic properties calculations

AU - Lambin, Philippe

AU - Amara, Hakim

AU - Ducastelle, Francois

AU - Henrard, L.

PY - 2012/7/27

Y1 - 2012/7/27

N2 - Being a true two-dimensional crystal, graphene has special properties. In particular, a pointlike defect in graphene may induce perturbations in the long range. This characteristic questions the validity of using a supercell geometry in an attempt to explore the properties of an isolated defect. Still, this approach is often used in ab initio electronic structure calculations, for instance. How does this approach converge with the size of the supercell is generally not tackled for the obvious reason of keeping the computational load to an affordable level. The present paper addresses the problem of substitutional nitrogen doping of graphene. DFT calculations have been performed for 9×9 and 10×10 supercells. Although these calculations correspond to N concentrations that differ by ∼10%, the local densities of states on and around the defects are found to depend significantly on the supercell size. Fitting the DFT results by a tight-binding Hamiltonian makes it possible to explore the effects of a random distribution of the substitutional N atoms, in the case of finite concentrations, and to approach the case of an isolated impurity when the concentration vanishes. The tight-binding Hamiltonian is used to calculate the STM image of graphene around an isolated N atom. STM images are also calculated for graphene doped with 0.5 at% concentration of nitrogen. The results are discussed in the light of recent experimental data and the conclusions of the calculations are extended to other point defects in graphene.

AB - Being a true two-dimensional crystal, graphene has special properties. In particular, a pointlike defect in graphene may induce perturbations in the long range. This characteristic questions the validity of using a supercell geometry in an attempt to explore the properties of an isolated defect. Still, this approach is often used in ab initio electronic structure calculations, for instance. How does this approach converge with the size of the supercell is generally not tackled for the obvious reason of keeping the computational load to an affordable level. The present paper addresses the problem of substitutional nitrogen doping of graphene. DFT calculations have been performed for 9×9 and 10×10 supercells. Although these calculations correspond to N concentrations that differ by ∼10%, the local densities of states on and around the defects are found to depend significantly on the supercell size. Fitting the DFT results by a tight-binding Hamiltonian makes it possible to explore the effects of a random distribution of the substitutional N atoms, in the case of finite concentrations, and to approach the case of an isolated impurity when the concentration vanishes. The tight-binding Hamiltonian is used to calculate the STM image of graphene around an isolated N atom. STM images are also calculated for graphene doped with 0.5 at% concentration of nitrogen. The results are discussed in the light of recent experimental data and the conclusions of the calculations are extended to other point defects in graphene.

UR - http://www.scopus.com/inward/record.url?scp=84864576576&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.86.045448

DO - 10.1103/PhysRevB.86.045448

M3 - Article

AN - SCOPUS:84864576576

VL - 86

JO - Physical Review B - Condensed Matter and Materials Physics

JF - Physical Review B - Condensed Matter and Materials Physics

SN - 2469-9950

IS - 4

M1 - 045448

ER -