Magnetism in strained graphene dots

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Viana Gomes, J (Author) Other; Pereira, VM (Author) Other; Peres, NMR (Author) Other

Journal

Title: Physical Review B - Condensed Matter and Materials Physics

Vol. 80

ISSN: 1098-0121

Publisher: American Physical Society

Indexing

ISI Web of Knowledge - 38 Citations

Scopus - 42 Citations

Other information

Authenticus ID: P-003-E5N

DOI: 10.1103/physrevb.80.245436

Abstract (EN): We study the magnetization of square and hexagonal graphene dots. It is shown that two classes of hexagonal dots have a second-order phase transition at a critical Hubbard energy U, whose value is similar to the one in bulk graphene, albeit the dots do not have a density of states proportional to the absolute value of the energy, relatively to the Dirac point. Furthermore, we show that a particular class of hexagonal dots, having zigzag edges, does not exhibit zero-energy edge states. We also study the effect of uniaxial strain on the evolution of the magnetization of square dots and find that the overall effect is an enhancement of magnetization with strain. The enhancement can be as large as 100% for strain on the order of 20%. Additionally, stress induces a spatial displacement of the magnetization over the dot, moving it from the zigzag to the armchair edges.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11