کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9567510 1503718 2005 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Scanning tunneling microscopy and spectroscopy studies of graphite edges
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Scanning tunneling microscopy and spectroscopy studies of graphite edges
چکیده انگلیسی
We studied experimentally and theoretically the electronic local density of states (LDOS) near single-step edges at the surface of exfoliated graphite. In scanning tunneling microscopy measurements, we observed the (3×3)R30° and honeycomb superstructures extending over 3-4 nm both from the zigzag and armchair edges. Calculations based on a density-functional-derived non-orthogonal tight-binding model show that these superstructures can coexist if the two types of edges admix each other in real graphite step edges. Scanning tunneling spectroscopy measurements near the zigzag edge reveal a clear peak in the LDOS at an energy below the Fermi energy by 20 meV. No such a peak was observed near the armchair edge. We concluded that this peak corresponds to the “edge state” theoretically predicted for graphene ribbons, since a similar prominent LDOS peak due to the edge state is obtained by the first principles calculations.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 241, Issues 1–2, 28 February 2005, Pages 43-48
نویسندگان
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