title: Subnanometric near-field Raman investigation in the vicinity of a metallic nanostructure.
abstract: We present a near-field Raman investigation in the subnanometric vicinity of a metallic nanotip, where the tip-sample distance is precisely controlled by our newly developed time-gated illumination technique. Using this scheme on an isolated carbon nanotube, we have profiled the spatial decay of evanescent light. We also investigated extremely short-ranged chemical and mechanical interactions between the metal on the tip apex and the molecules of an adenine sample, which are observable only within the subnanometric vicinity of the tip. The results show a near-field Raman investigation with an accuracy of better than a few angstroms. Further, this shows strong promise for superhigh resolution in optical microscopy based on this technique.
authors.affiliation: Department of Applied Physics, Osaka University, Osaka 565-0871, Japan and CREST, Japan. ichimura@ap.eng.osaka-u.ac.jp
authors.forename: Taro
authors.initials: T
authors.lastname: Ichimura
authors.forename: Shintaro
authors.initials: S
authors.lastname: Fujii
authors.forename: Prabhat
authors.initials: P
authors.lastname: Verma
authors.forename: Takaaki
authors.initials: T
authors.lastname: Yano
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Inouye
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kawata