Plasmon excitation surface

G. Gerber By applying two-photon ionization spectroscopy with tunable femtosecond laser pulses we recorded the absorption through intermediate resonances in cluster sizes Na with n = 3,. 21. The fragmentation channels and decay pattern vary not only for different cluster sizes but also for different resonances corresponding to a particular size n. This variation of r and the fragmentation channels cannot be explained by collective type processes (jellium model with surface plasmon excitation) but rather require molecular structure type calculations and considerations. 

Figure 11. SNOM and LELS. a) schematic SNOM experiment b) spectra following transmission enhancement via surface plasmon excitations, from [39] Copyright 1998 by the American Physical Society c) LELS simulation of a similar experiment for a fast (100 kV) electron.

Schaadt DM, Feng B, Yu ET (2005) Enhanced semiconductor optical absorption via surface plasmon excitation in metal nanoparticles. Appl Phys Lett 86(6) 063106... 

Highly enhanced local fields can be generated in the vicinity of a metallic spherical nanoparticle due to localized surface plasmon excitation. Using the result in Eq. (10b), the electric field components at the sur ce of the small sphere can be... 

Popov, E., Bonod, N., Neviere, M., Rigneault, H., Lenne, P., Chaumet, P. (2005). Surface plasmon excitation on a single subwavelength hole in a metal sheet. Appl. Opt. 44 2332-2337. 

In addition to dissociation and isomerization, the process of forming new chemical bonds and larger structures can also be enhanced or controlled with surface plasmon excitations. Here I would like to highlight the plasmon-assisted formation of rather larger structures than the simple molecular systems discussed so far metal nanoparticles themselves and polymeric materials. 

Hoheisel, W., Jungmann, K., Vollmer, M., Weidenauer, R. and Trager, F. (1988). Desorption stimulated by laser-induced surface-plasmon excitation. Phys. Rev. Lett. 60 1649-1652. 

Adrhodamine-B LB films due to surface plasmon excitations in the Kretschmann and reverse configurations. Mat. Res. Soc. Symp. 660 1-6. 

The electronic absorption spectrum of metal nanocrystals in the visible region is dominated by the plasmon band. This absorption is due to the collective excitation of the itinerant electron gas on the particle surface and is characteristic of a nanocrystal of a given size. In metal colloids, surface plasmon excitations impart characteristic colors to the metal sols, the beautiful wine-red color of gold sols being well-known [6-8]. The dependence of the plasmon peak on the dielectric constant of the surrounding medium and the diameter of the nanocrystal was predicted theoretically by Mie and others at the turn of the last century [9-12]. The dependence of the absorption band of thiol-capped Au nanocrystals on solvent refractive index was recently verified by Templeton et al. [13]. Link et al. found that the absorption band splits into longitudinal and transverse bands in Au nanorods [6, 7]. 

A. Ishida Y. Sakata T. Majima, Surface plasmon excitation of a porphyrin covalently linked to a gold surface. J. Chem. Soc., Chem. Comm 1998, 57-58. 

K. Saito, Quenching of excited J aggregates on metals by surface plasmon excitations. J. Phys. Chem. B 1999, 103, 6579-6583. 

The presence of interfaces within a polymer LED can also introduce additional nonradiative decay channels. This is particularly important in proximity to a metal electrode. Excitons which are able to diffuse to the metal surface are liable to be quenched directly by interaction with the metal wave function. This mechanism is therefore active only within a few nanometers of the interface. At larger distances (up to about 100 nm), excited molecules can couple to the surface plasmon excitations in the metal, thus providing a further nonradiative decay channel. The combined effects of changes in the radiative and nonradiative rates in two-layer LED structures have been modelled by Becker et al.,83 who have been able to model the variation in EL efficiency with layer thickness due to changes in the efficiency of exciton decay. 

Kretschmann E, Raether H (1968) Radiative decay of non radiative surface plasmons excited by light. Z Naturforschung A 23 2135-2142... 

Fig. 10 Instrumental contribution to sensitivity Skr/Sn f as a function of wavelength for an SPR sensor with wavelength modulation which employs symmetric (SSP) and antisymmetric (ASP) surface plasmons excited on a thin gold film using prism or grating coupler. Prism-based sensor configuration BK7 glass prism, buffer layer (refractive index 1.32), gold film (thickness 20 nm), and a non-dispersive dielectric (refractive index...

The potential of surface plasmons for optical sensing was recognized in the early 1980s when surface plasmons, excited in the Kretschmann geometry of the attenuated total reflection method, were used to probe processes at the surfaces of metals [1] and to detect gases [2]. Since then, numerous surface plasmon resonance (SPR) sensors have been reported. 

The resonance condition for surface plasmon excitation is found by setting the denominator in Eq. (14) to zero. 

In the present paper, we report on observation of the pronounced enhancement of photoluminescence of semiconductor nanocrystals near nanostructured metal surfaces which is shown to depend essentially on nanocrystal-metal spacing. Unlike conventional SERS, the surface enhanced PL should exhibit non-monotonous character with distance between emitting dipole (QD) and metal surface (Au colloid). The reason is that at smallest distances when QDs and colloidal particles are in close contact, the QD emission should be damped due to resonant energy transfer (RET) from photoexcited QDs to metal colloidal nanoparticles. Enhancement of photoluminescence (PL) is possibly promoted by surface plasmons excited in the metal. So, at a certain distance the enhanced QD emission would exhibit a maximum. We use a polyelectrolyte multilayers as the most appropriate... 

The key point is that the resonance wavelength of the surface plasmon excitation depends on a variety of parameters, such as size and shape of the particles as well as their arrangement and the dielectric properties of their environment [2,3]. One may therefore manipulate the optical behaviour of metal particle assemblies in order to prepare materials with tailored optical absorption properties. The purpose... 

Fundamentals. Surface plasmons (SP) can be used to monitor optical properties of metal and semiconductor surfaces. For introductory overviews, see [969, 970]. Surface plasmon field-enhanced light scattering (SPFELS) is observed when an interface is illuminated by light under conditions stimulating surface plasmon excitation as reported [971]. 

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