support from the National Key Research&Development Program(2015CB932700 and 2016YFA0201902);the National Natural Science Foundation of China(grant No.51290273,91433107,51325205 and 51521091);the Doctoral Fund of the Ministry of Education of China(grant No.20123201120026);ARC(DP140101501 and FT150100450);the Collaborative Innovation Center of Suzhou Nano Science&Technology;the Priority Academic Program Development of Jiangsu Higher Education Institutions;A*STAR Pharos Programme(grant No.1527000014,with Project No.R-263-000-B91-305);Competitive Research Program(CRP Award No.NRF-CRP15-2015-03);the National Research Foundation,Prime Minister’s Office,Singapore。
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...