Journal Club do Departamento de Física dos Materiais e Mecânica – FMT
Nesta semana o pós-graduando Rodrigo Mario Calle Huamani, do Laboratório de Materiais Magnéticos, apresentará o artigo: “Effects of edge on graphene plasmons as revealed by infrared nanoimaging”
Dia: 11 de outubro, quarta-feira, às 12h10.
Local: Sala de Seminários José Roberto Leite Edifício Alessandro Volta (bloco C).
Abstract:
We used scattering-type scanning near-field optical microscopy (s-SNOM) to investigate the plasmonic properties of edges in well-defined graphene nanostructures, including sharp tapers, nanoribbons and nanogaps, which were all fabricated via the growth-etching chemical vapor deposition (GECVD) method. The obtained near-field images revealed the localized plasmon modes along the graphene nanoribbon; these modes strongly depended on the size of the graphene pattern, the angle of the tapered graphene and the infrared excitation wavelength. These interesting plasmon modes were verified by numerical simulations and explained by the reflection, and interference of electromagnetic waves at the graphene–SiO2 edge. Theconstructive interference at the graphene nanogap caused by charge accumulation was demonstrated for the first time. Using the infrared nanoimaging technique, greater plasmon broadening was observed in the zigzag edge than in the armchair edge. Our study suggests that graphene edges should be separated by an effective working distance to avoid the overlapping of localized plasmon modes, which is very important for the design of graphene-based plasmonic circuits and devices. Light: Science & Applications (2017) 6, e16204; doi:10.1038/lsa.2016.204; published online 10 February 2017 Keywords: edge chirality; graphene; graphene plasmon; nanoribbon; nanogap; near-field microscopy; s-SNOM.
Link:
http://www.nature.com/lsa/journal/v6/n2/full/lsa2016204a.html http://www.nature.com/lsa/journal/v6/n2/pdf/lsa2016204a.pdf
