title: Nanofocusing of radially polarized light with dielectric-metal-dielectric probe.
abstract: Nanofocusing properties of a tip in the form of a dielectric tapered fiber with metal apertureless coating and dielectric nanocladding can be tuned within a wide spectral range by choice of cladding permittivity. The silica core of diameter decreasing from 2 mum to 5 nm in apex is covered with a silver layer and has a 5 nm dielectric cladding. Internal illumination with a radially polarized Laguerre-Gauss beam guided in fiber is used. In body-of-revolution finite-difference time-domain simulations we find that with an increase of the refractive index of nanocladdings the maximum enhancement occurs for increasingly longer wavelengths.
authors.affiliation: Faculty of Physics, University of Warsaw, Pasteura 7, 02-093 Warszawa, Poland. tantos@igf.fuw.edu.pl
authors.forename: Tomasz J
authors.initials: TJ
authors.lastname: Antosiewicz
authors.forename: Piotr
authors.initials: P
authors.lastname: Wróbel
authors.forename: Tomasz
authors.initials: T
authors.lastname: Szoplik
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008027:Light; D008670:Metals / Q000737:chemistry*; D055096:Optical Devices; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014159:Transducers
chemical_list: D008670:Metals