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Behavior of Mie Scattering for Spherical Particles for Range of Conditions

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Behavior of Mie Scattering for Spherical Particles for Range of Conditions International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 However, as the metallic rods (or nanoparticles) are absorbing, all the states in the blend will be decaying and eventually die off at the infinity. Yet all the Bloch eigenvalues in such systems have imaginary components. Our numerical calculations outline the importance of geometrical factors such as the size of the rods and their distribution. In particular, we have demonstrated, that interaction between adjacent nanorods brings the significant contribution to the transmission spectra, which is manifested as additional absorption peaks (that are missing in the effective-medium approach). The MG theory also disregards both the impacts of higher-order dipole contributions and formation of photonic band gaps in the case of arrays of large nanorods. Fig. 1. Transmittance, reflectance and absorption of a TE Fig. 2. Transmittance, reflectance and absorption of a mode travelling through the square arrays of nanorods single (a), a pair of horizontally (b) and vertically (c) with diameter aligned, and (d) four coupled nanorods for the TE- (a) 10 nm and (b) 60 nm. polarized light. 1. Dev et.al., Nanotechnology 17, 1533 (2006). 2. D. Losic et. al., Nanotechnology 16, 2275 (2005). 3. URL: http://www.sopra-sa.com/more/database.asp. 4. R. Quidant et. Al., Europhys. Lett. 66, 785 (2004). 5. M. Westphalen Sol. Energ. Mat. Sol. Cel. 61, 97, (2000). BEHAVIOR OF MIE SCATTERING FOR SPHERICAL PARTICLES FOR RANGE OF CONDITIONS Kenjaev Z.M.1,2, Mukimov K.M.1, Ramazonov A.Kh.1 1Institute of Applied Physics, National University of Uzbekistan, Tashkent, Uzbekistan 2Bukhara State University, Bukhara, Uzbekistan In present report we use Mie theory to study of light scattering on spherical particles for a range of conditions, including angular and size dependency. Based on the theory of Mie, the differential scattering cross sections are defined in terms of the angular intensity functions i1 and i2, as given by the expressions 219 Section II. Radiation Physics of Condensed Matter International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 Two equations are averaged to define the differential scattering cross section for unpolarized incident light, which gives the relation In this equation, the intensity functions are calculated from the infinite series given by In the equations (3) and (4), the angular dependent functions πn and n are expressed in terms of the Legendre polynomials by where the parameters an and bn are defined as The size parameter α is defined as The Ricatti-Bessel functions and are defined in terms of the half-integer-order Bessel function of the first kind ((Jzn + 1/ 2 )), where Eq.(10) describes the parameter where Hzn + 1/ 2 () is the half-integer-order Hankel function of the second kind, where the parameter Xn is defined in terms of the half-integer-order Bessel function of the second kind, Yn + 1/ 2 (z), namely Finally, the total extinction and scattering cross sections are expressed as 220 Section II. Radiation Physics of Condensed Matter International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 noting that the absorption cross section is readily calculated from the above two. Fig.2. The extinction efficiency as a function of Fig.1. Differential scattering cross-section as size parameter. a function of scattering angle . Fig.3. Differential scattering cross section at a fixed angle of 15o for vertical-vertical scattering as a function of scattering particle diameter for various particle refractive indices. METHODOLOGICAL AND TECHNICAL SOLUTIONS DURING PREPARATION FOR RADIATION HEATING-UP IN-PILE RESEARCHES Kadyrzhanov K.K., Kenzhin E.A., Izbaskhanova A.T. National Nuclear Center, Kurchatov, Kazakhstan In-pile research methods present more valuable and reliable information. During research performance special attention is paid to methodological and technical decisions making, which define conditions for in-pile experiments conduction. 221 Section II. Radiation Physics of Condensed Matter .
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