Complex refractive index calculated

The calculations assume semi-infinite first and last layers and a non-absorbing first layer. The complex refractive index of the yth layer is given by the following ... 

Fig. 6. Calculated ATR spectra (angle of incidence 45°) for a monolayer adsorbate (thickness tZ3 = 3 A) on a 20-nm-thick metal film in contact with a solvent as a function of the complex refractive index of the metal film. Sohd line parallel polarized light dotted line perpendicular-polarized light. The appropriate complex refractive index n2 is given at the top of each spectrum. The vertical bars indicate the scale for the absorbance, which is different for each spectrum. Parameters ni = 4.01 (Ge), n4 = 1.4 (organic solvent), rfs = 3 A, He = 1.6, S = 280000cm , Vo = 2000cm , y = 60cm . The parameters correspond to adsorbed CO. The calculations were performed by using the formalism proposed by Hansen (76), and the results are given in terms of absorbance A = —logio(7 /7 o), where 77 is the reflectivity of the system Ge/Pt/ adsorbate/solvent and Rg is the reflectivity of the system Ge/Pt/solvent (7S).

It should, however, be noted that there exist rather complex and nontransparent descriptions made [15] in terms of the absorption vibration spectroscopy of water. This approach takes into account a multitude of the vibration lines calculated for a few water molecules. However, within the frames of this method for the wavenumber1 v < 1000 cm-1, it is difficult to get information about the time/spatial scales of molecular motions and to calculate the spectra of complex-permittivity or of the complex refraction index—in particular, the low-frequency dielectric spectra of liquid water. 

Figure 29. Imaginary (a) and real (b) parts of the complex refraction index at 22.2°C. Ordinary water is represented by solid lines and circles, heavy water is represented by dashed lines and boxes. In the low-frequency region (for v < 20 cm-1), calculation is performed using approximation 17 modified as described in Appendix 3.2 in the rest region, it is performed using the recorded data [51] given in Table XI.

Figure 27 Schematic representation of the all-optical parallel processing in guided mode geometry and the calculated reflectance for a polymer film (1600 nm) on a silver layer (50 nm). The complex refractive index of a polymer layer is (a) 1.60, (b) 1.58, and (c) 1.60 + 0.02i.

The reflectivity spectra R(E) and the reflectivity-EXAFS Xr(E) = R(E) — Rq(E)]/R()(E) are similar, but not identical, to the absorption spectra and x(E) obtained in transmission mode. R(E) is related to the complex refraction index n(E) = 1 — 8(E) — ifl(E) and P(E) to the absorption coefficient /i(E) by ji fil/An. P and 8 are related to each other by a Kramers-Kronig transformation, p and 8 may be also separated in an oscillatory (A/ , AS) and non-oscillatory part (P0,80) and may be used to calculate Xr- This is, briefly, how the reflectivity EXAFS may be calculated from n(E). which itself can be obtained by experimental transmission EXAFS of standards, or by calculation with the help of commercial programs such as FEFF [109] with the parameters Rj, Nj and a, which characterize the near range order. The fit of the simulated to measured reflectivity yields then a set of appropriate structure parameters. This method of data evaluation has been developed and has been applied to a few oxide covered metal electrodes [110, 111], Fig. 48 depicts a condensed scheme of the necessary procedures for data evaluation. 

The above relationships (Figure 1.10) show that the optical pigment properties depend on the particle size D and the complex refractive index n = n (1 - i/c), which incorporates the real refractive index n and the absorption index k. As a result, the reflectance spectrum, and hence the color properties, of a pigment can be calculated if its complex refractive index, concentration, and particle size distribution are known [1.40]. Unfortunately, reliable values for the necessary optical constants (refractive index n and absorption index k) are often lacking. These two parameters generally... 

Inside this cloud the size distribution of particles can be characterized by normal-logarithmic distribution with r = 0.25 ftm, cr = 2.0 (for particles with r < 3 tim) and the power law (y = 4.0), to describe the trail of distribution in the range of particle sizes 3 — 1,000 M-m. Cn values in such clouds are greatest for the submicron fraction. About 8% of the total SDA mass in the cloud are assumed to be particles with r < 1 p.m. The complex refractive index, m of dust particles in clouds is assumed to be 1.5-O.OOli [38]. Figure 1 shows model temporal dependences of the vertical optical thickness, c, of a post-nuclear dust cloud, calculated for the Northern Hemisphere [38]. As is seen, "c values (0.55 (tm), immediately upon the formation of the cloud, can vary from 0.25 to 3, depending on the SDA mass concentration in the cloud and on its size distribution. 

Figure 4 shows theoretical losses of (1) silver hollow-optical fiber, (2) dielectric-coated silver hollow-fiber with coating thickness of 0.39 pm, and (3) d = 0.66 pm. The thickness of 0.39 pm is the optimized value for 2 = 3 pm and 0.66 pm is the one for 2 = 5 pm. Parameters used in the calculation are rii = 1.53, z = 1 m, 2T = 1 mm, and cr = 0 and complex refractive index of silver is taken from literature [11]. In the calculation, a Gaussian beam with the divergence angle of 6° in full-width-half-maximum is assumed as an input beam. As seen from the calculated spectra, one can obtain a low loss region around the optimized wavelength. 

Figures 7 and 8 show two different designs with a different number of layers in the metal-dielectric AR part of the structure, along with their calculated performances (reflectance and luminance spectra). The complex refractive index of all layers were measured from films deposited in the same conditions as our devices. When compared to the performance of a conventional OLED shown in Fig. 3(b) and (c), we see that the new designs reduce the reflectance to 2% and less, which is 25 times less than that of a typical OLED, and that the emission is of the same order of magnitude.

The thickness of the interface layer where the dopant concentration is different from that of the bulk is roughly estimated as follows. Since a molar extinction coefficient of carbazolyl chromophore in PVCz at 295 nm is 1.54 x 10 cra M", the depth where the excitation intensity is 1/e of the initial value is calculated to be 0.065 um under the normal condition. On the other hand, the penetration depth of the evanescent wave is a function of the incident angle, and it is difficult to calculate it here because the complex refractive index cannot be estimated correctly from the large absorbance at the laser wavelength. At present we can say that the TIR phenomenon was really observed and that the effective thickness under the TIR... 

The authors used these difference spectra as a basis for comparison with their calculations of the contribution to A R/R which may result from the variation of the proton excess in the double layer. Sulphate ions have only a minor influence on the -OH absorption spectrum of water [41] and the authors decided that the HS04" ion present at the low pH employed in the experiment would not behave much differently. Since the same is true for the Cl" ion, the authors used optical data which was available for different concentrations of HC1 [42] in their model calculations. The imaginary part of the complex refractive index, k, was plotted [22] for HC1 solutions in H20 in the spectral range of interest ( 3000 cm"1). The effect of increasing... 

Thus, we can calculate the imaginary part of the complex refractive index of a dielectric medium if we know the extinction coefficient and concentration of the absorbing species. If the lower index medium in a total internal reflection configuration has a complex refractive index, that is it is lossy, then the reflection coefficient is reduced from unity, even for angles of incidence above the critical angle. 

An obvious attractive feature of ellipsometry is that two parameters are obtained in a single measurement. If there is only one perfectly homogeneous surface with a complex refractive index, the real and complex part of the refractive index can be calculated from the two ellipsometric angles. The situation becomes more complicated if the assumed system becomes more complicated every thin film has a thickness and a complex refractive index, which means three additional parameters. 

Figure 3.67. Calculated p- (solid lines) and s-(dotted lines) ATR spectra for monolayer adsorbate on 20-nm metal film in contact with solvent as function of complex refractive index of metal film. Except for metal, the system is as in Fig. 3.236, c. The respective complex refractive index of metal film is given at top part of each spectrum. Reprinted, by permission of the Royal Society of Chemistry on behalf of the PCCP Owner Societies, from T. Burgi, Phys. Chem. Chem. Phys. (PCCP) 3,2124 (2001), p. 2128, Fig. 10. Copyright 2001 The Owner Societies.

The optical absorption coefficient a, calculated from the complex refractive index or dielectric constant of the film on Pt, exhibits two peaks at 3 00 and 365 mm, as pointed out by McIntyre and Kolb on the basis of their specular reflectance spectroscopic measurements over the wavelength range... 

Fig. 4.1-161 ZnO. Numerically calculated spectral dependence of the complex refractive index n = n E) + ik(E) for ZnO (solid lines). The circles represent experimental data at 300 K [1.136]...

In order to calculate the optical generation rates in the organic absorbers (see appendix 1), it is necessary to determine the complex refractive index n = n + ik of all layers. The most useful method to obtain this data is spectroscopic ellipsometry, which allows us to determine the real part n and imaginary part k of the refractive index. The general measurement principle of ellipsometry is to measure the polarization of an output beam after the polarized input beam has interacted with the sample. From the change in polarization we derive the optical properties of the layer by fitting the measured output polarization to a model of the optical response of the material [144]. 

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