Plasmon structures

Nordlander, P., and Le, F. 2006. Plasmonic structure and electromagnetic field enhancements in the metallic nanoparticle-film system. Appl. Phys. B 84 35 1. 

W., and Odom, T.W. (2009) Nanofabrication of plasmonic structures. Annual Review of Physical Chemistry, 60, 147-165. 

Barrow, S.J., Funston, A.M., Wei, X., Mulvaney, P., 2013. DNA-directed self-assembly and optical properties of discrete ID, 2D and 3D plasmonic structures. Nano Today 8 (2), 138-167. 

M.J. Mulvihill, X.Y. Ling, J. Henzie, and P. Yang, Anisotropic etching of silver nanoparticles for plasmonic structures capable of single-particle SERS, J. Am. Chem. Soc., 132, 268-274, 2009. 

Gehan H., L. Fillaud, M. M. Chehimi, J. Aubard, A. Hohenau, N. Felidj, C. Mangeney. Thermo-induced electromagnetic coupling in gold/polymer hybrid plasmonic structures probed by surface-enhanced Raman scattering. ACS Nano 4, 2010 6491-6500. 

The existence of designer SPP is extremely important for infrared photodetectors. One is able to fabricate any desired plasmonic structure and to tune it for the targeted wavelength range. As an example, infrared detectors enhanced by designer plasmon structures tuned to the range of 8-10 pm have been reported [311]. 

It is important to note that the refractive index is 8—20% lower than the corresponding bulk material thus, 1ow-m materials can be easily and reproducibly obtained with a MTF by tuning the relative hiunidity. Therefore, the control of thickness and refractive index of MTFs opens new chances in the design of new optical structures with novel and special properties, such as plasmonic devices, low- waveguides, photonic crystals, or composed photonic-plasmonic structures. 

LSPR frequency is dependent on the size, shape, material properties and the effect of the dielectric medium around the nanoparticles. They determine the position and width of the plasmon resonance. Due to the confinement of the SP to the metal nanoparticle, excitation of surface plasmons can result in selective photon absorption, scattering and a large enhancement of the local electric field in the close vicinity of the metal nanoparticles. Hence, varying these parameters offers the tunable resonance position to engineer plasmonic structures to target weakly absorbing regimes of various types of solar cells [5]. 

As discussed in previous sections, plasmonic structures improve the absorption efficiency of the photovoltaic absorber layers by preferentially scattering [40] and exciting localized surface plasmons [12, 41] or plasmon polaritons [42-46]. Surface plasmons are localized by noble metallic nanoparticles (NPs) such as Cu [47-49], Ag and Au resulting in localized surface plasmon resonance (LSPR). Ag and Au NPs are the most widely used materials due to their surface plasmon resonances located in the visible range. A1 and Cu, which have resonance in the ultraviolet and... 

The inclusion of sub-wavelength plasmonic particles and other plasmonic structures in solar cells has been shown to reduce notably the required thickness of the photoactive layer and to expand greatly the pool of its usable absorber materials. For most plasmon-enhanced solar cells, fabrication only involves... 

Figure 2.36 A shows a typical low-loss spectrum taken from boron nitride (BN). The structure of BN is similar to that of graphite, i. e. sp -hybridized carbon. For this reason the low-loss features are quite similar and comprise a distinct plasmon peak at approximately 27 eV attributed to collective excitations of both n and a electrons, whereas the small peak at 7 eV comes from n electrons only. Besides the original spectrum the zero-loss peak and the low-loss part derived by deconvolution are also drawn. By calculating the ratio of the signal intensities hot and Iq a relative specimen thickness t/2 pi of approximately unity was found. Owing to this specimen thickness there is slight indication of a second plasmon.

Dravid et al. examined anisotropy in the electronic structures of CNTs from the viewpoint of momentum-transfer resolved EELS, in addition to the conventional TEM observation of CNTs, cross-seetional TEM and precise analysis by TED [5]. Comparison of the EEL spectra of CNTs with those of graphite shows lower jc peak than that of graphite in the low-loss region (plasmon loss), as shown in Fig. 7(a). It indicates a loss of valence electrons and a change in band gap due to the curved nature of the graphitic sheets. 

Although CNTs showed similar EELS pattern in plasmon-loss and core-loss regions to graphite, SWCNT and fine MWCNT with a diameter less than 5 nm had different features. Furthermore, it has been found out that the angular-dependent EELS along the direction normal to the longitudinal axis of CNT shows stronger contribution from Jt electrons than [Pg.38]

More recently, the method of scanning near-field optical microscopy (SNOM) has been applied to LB films of phospholipids and has revealed submicron-domain structures [55-59]. The method involves scanning a fiber-optic tip over a surface in much the same way an AFM tip is scanned over a surface. In principle, other optical experiments could be combined with the SNOM, snch as resonance energy transfer, time-resolved flnorescence, and surface plasmon resonance. It is likely that spectroscopic investigation of snbmicron domains in LB films nsing these principles will be pnrsned extensively. 

A large number of possible applications of arrays of nanoparticles on solid surfaces is reviewed in Refs. [23,24]. They include, for example, development of new (elect-ro)catalytical systems for applications as chemical sensors, biosensors or (bio)fuel cells, preparation of optical biosensors exploiting localized plasmonic effect or surface enhanced Raman scattering, development of single electron devices and electroluminescent structures and many other applications. 

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