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Evlyukhin A.B.,Laser Zentrum Hannover e.V. | Evlyukhin A.B.,Kama State Academy of Engineering and Economics | Reinhardt C.,Laser Zentrum Hannover e.V. | Seidel A.,Laser Zentrum Hannover e.V. | And 2 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

Periodic structures of spherical silicon particles are analyzed using the coupled-dipole equations for studying optical response features and local electromagnetic fields. The model takes into account the electric and magnetic dipole moments of the particles embedded in a homogeneous dielectric medium. Particles with radius of 65 nm and larger are considered. It is shown that, due to the large permittivity of silicon, the first two Mie resonances are located in the region of visible light, where the absorption is small and the extinction is basically determined by scattering. The main contribution is given by the induced magnetic and electric dipoles of the particles. Thus, in contrast to metal particle arrays, here is a possibility to combine separately either the electric or magnetic dipole resonances of individual particles with the structural features. As a result, extinction spectra can have additional narrow resonant peaks connected with multiple light scattering by the magnetic dipoles and displaying a Fano-type resonant profile. Reflection and transmission properties of the Si particle arrays are investigated and the conditions of low light reflection and transmission by the particle arrays are discussed, as well as the applicability of the dipole approach. It is shown that the light transmission of finite-size arrays of Si particles can be significantly suppressed at the conditions of the particle magnetic dipole resonance. It is demonstrated that, using resonant conditions, one can separately control the enhancements of local electric and magnetic fields in the structures. © 2010 The American Physical Society.


Stepanov A.L.,Laser Zentrum Hannover e.V. | Stepanov A.L.,Kazan Federal University | Galyautdinov M.F.,Russian Academy of Sciences | Evlyukhin A.B.,Laser Zentrum Hannover e.V. | And 8 more authors.
Applied Physics A: Materials Science and Processing | Year: 2013

Ion implantation was used to locally modify the surface of silica glass to create periodic plasmonic microstructures with Cu nanoparticles. Nanoparticles were synthesized by Cu-ion irradiation of the silica glass at the ion energy of 40 keV, dose of 5×1016 ions/cm2 and current density of 5 μA/cm2. This procedure involves low-energy ion implantation into the glass through a mask placed at the surface. Formation of nanoparticles was observed by optical spectroscopy and atomic force microscopy. The presented results clearly demonstrate how the low-energy ions can be used for the fabrication of photonic microstructures on dielectric surfaces in a single-step process. © 2012 Springer-Verlag Berlin Heidelberg.


Novikov S.M.,University of Southern Denmark | Evlyukhin A.B.,Laser Zentrum Hannover e.V. | Evlyukhin A.B.,Kama State Academy of Engineering and Economics | Kuznetsov A.I.,Laser Zentrum Hannover e.V. | And 4 more authors.
Journal of the Optical Society of America B: Optical Physics | Year: 2012

Field intensity enhancements (FEs) produced by gold needle nanostructures, namely, standing upright sharp and sphere-terminated needles, fabricated on a gold substrate by femtosecond laser irradiation, are investigated and characterized using linear reflection spectroscopy, two-photon photoluminescence (TPL) scanning optical microscopy, and high-resolution confocal Raman microscopy. Surface enhanced Raman scattering (SERS) is observed using linearly polarized 532 nm excitation of Rhodamine 6G homogeneously adsorbed on the structures. The obtained high-resolution TPL and Raman images both indicate a relatively high FE level of -75 for the fabricated structures. We believe that the observed FE levels along with the special topography make these upright elongated structures particularly promising for SERS experiments with living cells. © 2011 Optical Society of America.


Adgamov R.I.,Kazan State Technological University | Dmitriev S.V.,Kama State Academy of Engineering and Economics | Khairullin A.Kh.,Kama State Academy of Engineering and Economics
Russian Aeronautics | Year: 2012

The quality control system for an aircraft engine that is continuously developed in the life cycle stages is considered. Main quality indicators and their control methodology are analyzed. The computer-aided tests are substantiated as part of the quality control system and their generalized technological process structure and its construction methodology are proposed. © 2012 Allerton Press, Inc.


Sibgatullin K.E.,Kama State Academy of Engineering and Economics | Sibgatullin E.S.,Kama State Academy of Engineering and Economics
Mechanics of Solids | Year: 2010

We consider bars of arbitrary shape made of a homogeneous anisotropic material. In the general case, all six internal force factors (three forces and three moments) are simultaneously nonzero in the transverse cross-sections of the bar. We consider the case of small displacements and strains of the bar. Using the rigid-plastic model of a strained rigid body, the associated strain law, and the traditional hypotheses of static and kinematic character for the bars, we derive parametric equations for the limit surface (the strength surface) in the space of internal forces and moments acting in the the transverse cross-section. We present several versions of the obtained equations in specific cases (for orthotropy, transversal isotropy, and isotropy) and some numerical examples. © Allerton Press, Inc., 2010.

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