Paper
18 August 2005 Optical properties of the tips for apertureless near-field microscopy
Author Affiliations +
Abstract
The local electric field enhancement in the vicinity of a metal-coated or metal tip is a significant factor in the performance of apertureless near-field optical microscopy and spectroscopy techniques. Enhancement, which is related to the generation of localized surface plasmons in the metal tip, can be maximized when the plasmons resonate at the probing wavelength. Thus the resonance frequencies of the tip apex are crucial to near-field optics. However, it remains a challenge to measure the optical properties of the apex of a tip with a radius much smaller than the wavelength of light. A dark-field scattering spectroscopy method is presented in combination with a side-illumination nano-Raman spectrometer to experimentally determine the optical properties of the tip. The dependence of the optical resonance on the metal deposited is shown for silver- and gold-coated tungsten tips as well as gold-coated silicon nitride tips. The enhancement for Si using gold-coated silicon nitride tips is somewhat larger for a wavelength of 647 nm than for a wavelength of 514.5 nm. The former is closer to the plasmon resonance observed for this tip at ~680 nm.
© (2005) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
D. Mehtani, N. Lee, R. D. Hartschuh, A. Kisliuk, M. D. Foster, A. P. Sokolov, and I. Tsukerman "Optical properties of the tips for apertureless near-field microscopy", Proc. SPIE 5927, Plasmonics: Metallic Nanostructures and Their Optical Properties III, 59270K (18 August 2005); https://doi.org/10.1117/12.615421
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Silicon

Tungsten

Near field optics

Optical properties

Metals

Scattering

Spectroscopy

Back to Top