Attenuated total reflection configurations

Evaporated silver films on gratings at room temperature is another interesting layout. It was applied mostly by Tsang et 54,170,175,176 ATR (attenuated total reflection) configur-... 

Figure 3 Typical beam path configuration for collecting an FTIR spectrum using an attenuated total reflectance element Iq is the incident infrared beam, f is the exiting beam.

The single prism measurements can also be done using the configuration shown in Fig. 9. Here the thin metal film itself on the prism base serves as the low index gap for exciting SEW on the metal-air interface below. This type of attenuated total reflection excitation of surface waves was first used by... 

Adsorption of CN on a silver metal film was reported by Hatta et al. [112], using multiple internal reflection in an ATR (attenuated total reflection) prism configuration. Basically the same features were observed by Hatta et al. as in the external reflection approach, namely a potential-dependent band located between 2100 and 2118 cm assigned to the adsorbed CN ion and another band located at 2143 cm , assigned to the Ag(CN)2 complex. The feature at 2167 cm was not observed, because of the limited potential range used in this experiment to avoid the dissolution of the silver film [112]. 

Thus, surface plasmons (SPs) are excited on the dielectric medium - metal interfoce through evanescent wave excitation by attenuated total reflection (ATR) (23, 33, 36-38). One can excite SPs through the Kretschmann-Raether configuration... 

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. 

The most common approach to excitation of surface plasmons is by means of a prism coupler and the attenuated total reflection method (ATR). There are two configurations of the ATR method - Kretschmann geometry [5] and... 

A) Transmission probe with facing configuration, (B) Transmission probe with side-by-side configuration, (C) Attenuated total reflectance (ATR) probe, (D) Scattering probe. 

Reflection measurements at optically flat interfaces can be performed in two basic configurations, external and internal reflection. In the case of external reflection (also called specular reflection) the light propagates in the optically rare medium (e. g. air), whereas in the case of internal reflection (usually employed as attenuated total reflection (ATR)) the hght propagates in the optically dense medium (Fig. 5.3). 

The combination of infrared spectroscopy with the theories of reflection has made advances in surface analysis possible. Attenuated Total Reflectance (ATR) spectroscopy is an innovative technique for proving chemical information of a sample surface and the ability to quantify newly formed species, based upon Pick s second law. The fundamentals of attenuated total reflection (ATR) spectroscopy date back to the initial work of Jacques Fahrenfort and N.J. Harrick, both of whom independently devised the theories of ATR spectroscopy and suggested a wide range of applications. The schematic showing ATR-FTIR configuration is illustrated in Fig. 1 (KS. Kwan, 1998). The penetration depth, d, can be estimated as ... 

Optical Operation Modes Fig. 8 illustrates five types of light incident and collection configurations for the Raman study of an electrode surface. They can be classified into three general kinds of operation modes front incident and collection mode back-scattering mode and the attenuated total reflection (ATR) mode. 

There are two main configurations with regards to the prism coupling technique Kretschmann configuration and Otto configuration. Optical excitation of SPs by the method of attenuated total reflection was demonstrated by Kretschmann and Otto... 

Fig. 1 shows the Kretschmann configuration of the attenuated total reflection (ATR) method. The ATR method was reported in previous papers [l]-[6]. An Ar laser beam at 488.0 nm was used to excite SPs on metal thin films in this measurement and the p-polarized beam was directed onto the samples on the substrates through the half-cylindrical prism. The prism was mounted on a rotating stage. The incident angles of the laser beam were scanned using a computer-controlled pulse motor. The reflected intensities of the laser light, that is, the ATR... 

Figure 1(a) shows the Kretschmann configuration [9] for the excitation of plasmon surface polaritons (surface plasmons for short) [10] in the attenuated total reflection (ATR) mode. When a p-polarized laser beam is irradiated at the (internal) incident angle 9t from the prism of a refractive index np above 6c, a strong nonradiative electromagnetic wave, i.e. a surface plasmon is excited at the resonant angle which propagates at the metal /electrolyte interface. 

Figure 3 shows an attenuated total reflection (ATR) setup for the excitation of surface plasmons in the Kretschmann configuration combined with an electrochemical cell. 

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