Surface Plasmon Polariton Spectroscopy

In Section 4.3 we have considered surface polariton spectroscopy in the infrared region. As distinct from that case, SPs in the optical spectral range exist mainly on metal surfaces, i.e., as surface plasmon polaritons (SPP). The SPP dispersion curve extends from the far-infrared up to the far-ultraviolet region and thus it can be excited at any frequency in this range. This allows one to use SPPs as an optical probe of various overlayers on metal surfaces and in- 

4) Another example is surface exciton polaritons on semiconductor surfaces. 

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Hayazawa, N., Ishitobi, H., Taguchi, A., Ikeda, K., Tarun, A., and Kawata, S. 2007a. Focused excitation of surface plasmon polaritons for efhcient held enhancement based on gapmode in tip-enhanced spectroscopy. Jpn. J. Appl. Phys. 46 7995-99. 

At the surface of metals, the surface plasmon-polaritons, also called "surface plasmons," are not the same as the "bulk" plasmons these surface plasmons are affected (i.e., shifted slightly in energy) by monolayer adsorbates thus Surface Plasmon Resonance (SPR) spectroscopy yields information about the nature of the binding of the adsorbates onto a metal surface. The surface plasmons are excited by a p-polarized electromagnetic wave (polarized in the plane of the film) that crosses a glass medium (1), such as a prism, and is partially reflected by a metallic film (2) and back into the glass medium the dispersion relation is... 

Instrumentation. In order to employ local enhancement of infrared absorption by surface plasmon polaritons that cause locally enhanced surface electromagnetic fields, a suitable optical arrangement is needed [295]. Surface enhanced infrared absorption spectroscopy can also be observed in the transmission mode [285, 296]. However, since no application of this approach in spectroelectrochemistry has been reported so far, it is not discussed further. 

The application of the ATR method in Raman spectroscopy provides a unique way to study essentially mirrorlike polished metals, in particular single crystalline surfaces. The ATR method is used to excite surface plasmon polaritons (SPPs) effectively at the smooth metal surface, to improve the sensitivity in Raman spectroscopy by electromagnetic field enhancement [19]. The enhancement of the ATR configuration, as shown in Figs. 8(d and e), with respect to the normal external reflection geometry spans one to three orders, depending on the electrodes and their crystallographic orientations. 

Brioude, A., Lequevre, F., Mugnier, J., Bovier, C, Dumas, J., and Plenet, J.C. (2002) Densification and nanocrystallisation of sol-gel Zr02 thin films studied by surface plasmon polariton-assisted Raman spectroscopy. Eur. Phys. J. B, 26,115-119. 

In the experimental study of surface excitons various optical methods have been used successfully, including the methods of linear and nonlinear spectroscopy of surface polaritons. A particularly large body of information has been obtained by the method of attenuated total reflection of light (ATR), introduced by Otto (1 2) (Fig. 12.1) to study surface plasmons in metals. Later the useful modification of ATR method also was introduced by Kretschmann (3) (the so-called Kretschmann configuration, see Fig. 12.2). The different modification of ATR method has opened the way to an important development in the optical studies of surface waves and later was used by numerous authors for investigations of various surface excitations. 

Knobloch, H., Brunner, H., Leitner, A., Aussenegg, F., and Knoll, W. (1993). Probing the Evanescent Field of Propagating Plasmon Surface-Polaritons by Fluorescence and Raman Spectroscopies Journal (rf Chemical Physics 98 10093-10095. 

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