Superfocusing by nanoshells

Superfocusing by nanoshells.

Recently researchers demonstrated, both theoretically and in the microwave range experimentally, subwavelength focusing of evanescent waves by patterned plates. The present Letter extends these ideas and the design procedure to scatterers of arbitrary shapes and to the optical range of wavelengths. The analytical study is supported by numerical results. The most intriguing feature of the propos...

Acoustically propelled nanoshells.

Herein we report a new design for acoustic nanoswimmers, making use of a nanoshell geometry that was synthesized using a sphere template process. Such shell-shaped nanomotors display highly efficient acoustic propulsion on the nanoscale by converting energy from the ambient acoustic field into motion. The propulsion mechanism of the nanoshell motors relies on acoustic streaming stress over the ...

Optimization of plasmonic heating by gold nanospheres and nanoshells.

Gold nanoparticles have strong and tunable absorption peaks in their optical extinction spectra, a phenomenon that has recently been exploited to generate localized heating in the vicinity of these particles. However the optimum particle geometry and illumination regime to maximize these effects appears not to have been previously examined in any detail. Here we show that the interplay between ...

Carbon onions within silica nanoshells

Carbon onions have been known since Iijima first observed them in 1980 [1]. In 1992 Ugarte et al. made carbon onions by irradiating carbon soot by an intense electron beam in a transmission electron microscope [2]. There are reports in the literature on the production of carbon structures in water medium by generating an electric arc to create high temperatures [3,4]. It was found that several ...

Gold Nanoshells in Biomedical Applications