Localized plasmon resonance

Near-Field Optical Imaging of Localized Plasmon Resonances in Metal Nanoparticles... 

Localized plasmon resonance on noble metal nanostructures Noble metal nanostructures exhibit a strong UV visible extinction band with its peak position affected by the dielectric constant and thickness of the material surrounding the nanostructures 7,11 13... 

Fig. 12.4. Suggestive set-ups for detection of mercury vapour by surface plasmon resonance (left) and localized plasmon resonance (right). The simplest configurations are shown a higher sensitivity can be obtained by using double wavelength technique [28], distributed referencing [29], bimetallic resonant mediums [26], or other approaches.

Another plasmon resonance approach for detection of mercury vapour is based on localized plasmon resonance in gold nanoparticles deposited on transparent support (Fig. 12.4, right). Changes of the refractive index of gold nanoparticles due to adsorption of mercury should lead to modification of the gold plasmon band of optical adsorption spectra. This approach has been applied successfully for investigation of interaction of biomolecules however, to our knowledge there is still no report on its applications for detection of mercury vapour. 

Localized plasmon resonance 240 Locally modified surfaces 922 Lysine 256 Lysozyme 815... 

Common methods for the fabrication of metallic nanoparticle arrays are electron beam lithography, photolithography, laser ablation, colloidal synthesis, electrodeposition and, in recent time, nanosphere lithography for which a monodisperse nanosphere template acts as deposition mask. A review on advances in preparation of nanomaterials with localized plasmon resonance is given in [15]. 

The heart of the TERS technique is a hof tip, which can highly confine and enhance the electric field at the tip apex. A brief introduchon of the origins of the field enhancement is now given here. There are two main types of field enhancement (i) that powered by localized plasmon resonance which is highly frequency-dependent and (ii) shape-induced enhancement which does not depend on the frequency. To yield a good enhancement, one can either tune the excitation wavelength to coincide with the resonant frequency (or vice versa), or use a structure which can provide enhancement over a wide spectral range. 

Fig. 6.30 (a) Schematic illustration of processes of surface-plasmon resontince (SPR) and localized-plasmon resonance (LPR). (b) Photocurrent ratio of a ruthenium dye (N3)-modified nanostructured electrode (SPR) to planar electrodes (LPR) (filled circle), and the transmission absorption spectrum (solid line) of the nanostructured electrode [138]... 

The nanoparticles of precious metals possess the unique optical properties connected with the presence of one or several resonance peaks in visible and near IR-area in absorption spectrum. These peaks are caused by so-called localized plasmon resonances. Plasmon resonance peaks are the result of excitation of... 

Beer-Lambert law. This approach is particularly germane to metal NPs such as Au and Ag, which support localized plasmon resonances at visible wavelengths [16],... 

Fig. 8.2 (a) Calculated localized plasmon resonance at the ends (indicated by stars) of a nanosphere (10 nm diameter) and nanorods (20 and 30 nm long by 10 nm wide) made of aluminum and silver. The solid and dashed lines represent the spectra for aluminum and silver, respectively. (b)-(d) Calculated field distributions near the aluminum nanoparticles in the plasmon resonance of the 10-nm-diameter nanosphere, 20-nm-long nanorod, and the 30-nm-long nanorod, respectively... 

The main electromagnetic field enhancement is now considered to come from a geometrically defined localized plasmon resonance within metal particles such as produced by an ORC pretreatment in an electrochemical system. 

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