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    All optical switch based on Fano resonance in metal nanocomposite photonic crystals

    , Article Optics Communications ; Volume 284, Issue 8 , 2011 , Pages 2230-2235 ; 00304018 (ISSN) Asadi, R ; Malek Mohammad, M ; Khorasani, S ; Sharif University of Technology
    Abstract
    We investigate the potential of plasmonic resonance in metal nanocomposite materials for the design of photonic crystal all optical switches by numerical methods. We study the absorption effect of the plasmonic resonance on the Fano resonances of one dimensional photonic crystal slabs covered by a metal nanocomposite layer. It is shown that the absorption reduces the contrast of the Fano resonances. However, for adequate metal nanoparticle concentrations it is possible to achieve both sufficiently sharp Fano resonance and strong Kerr nonlinearity, which provides a suitable condition for the design of high contrast and low threshold switches  

    Highly biocompatible multifunctional hybrid nanoparticles based on Fe3O4 decorated nanodiamond with superior superparamagnetic behaviors and photoluminescent properties

    , Article Materials Science and Engineering C ; Volume 114 , September , 2020 Salkhi Khasraghi, S ; Shojaei, A ; Sundararaj, U ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    The multifunctional nanostructures with superparamagnetic and luminescent properties undergo revolution in the field of bio-nanotechnology. In this article, we reported a facile and efficient one-step modified co-precipitation method to load superparamagnetic Fe3O4 nanoparticle on oxidized nanodiamond (Ox-ND). Subsequently, the as-prepared Ox-ND/Fe3O4 hybrid nanoparticle was surface functionalized with vinyltrimethoxysilane (VTMS) to enhance its compatibility with organic media. The structure, morphology, magnetic, and optical properties of the nanohybrid were systematically investigated. The results confirmed successful loading of crystalline Fe3O4 on the surface of Ox-ND. Ox-ND/Fe3O4... 

    Sensitivity analysis of atomic force microscope cantilever made of functionally graded materials

    , Article Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference 2009, DETC2009, 30 August 2009 through 2 September 2009 ; Volume 6 , August , 2010 , Pages 539-544 ; 9780791849033 (ISBN) Rahaeifard, M ; Kahrobaiyan, M. H ; Ahmadian, M.T ; Sharif University of Technology
    2010
    Abstract
    The purpose of this paper is the enhancement of the AFM sensitivity through the selection of an optimized FGM micro cantilever beam. In this paper, resonant frequencies and sensitivities of first two modes of micro cantilever which is made of functionally graded materials are investigated and a relationship is developed to evaluate the sensitivity of FGM micro cantilever. Effect of volume fraction of materials and surface contact stiffness on the resonant frequencies and sensitivities are studied. The rectangular FGM beam is modeled by an Euler-Bernoulli beam theory. It is assumed that beam is made of a mixture of metal and ceramic with properties varying through the thickness following a... 

    Sensitivity analysis of atomic force microscope cantilever made of functionally graded materials

    , Article Proceedings of the ASME Design Engineering Technical Conference, 30 August 2009 through 2 September 2009, San Diego, CA ; Volume 6 , 2009 , Pages 539-544 ; 9780791849033 (ISBN) Rahaeifard, M ; Kahrobaiyan, M. H ; Ahmadian, M. T ; Sharif University of Technology
    ASME  2009
    Abstract
    The purpose of this paper is the enhancement of the AFM sensitivity through the selection of an optimized FGM micro cantilever beam. In this paper, resonant frequencies and sensitivities of first two modes of micro cantilever which is made of functionally graded materials are investigated and a relationship is developed to evaluate the sensitivity of FGM micro cantilever. Effect of volume fraction of materials and surface contact stiffness on the resonant frequencies and sensitivities are studied. The rectangular FGM beam is modeled by an Euler-Bernoulli beam theory. It is assumed that beam is made of a mixture of metal and ceramic with properties varying through the thickness following a... 

    Optimization of first mode sensitivity of V-shaped AFM cantilever using genetic algorithm method

    , Article ASME International Mechanical Engineering Congress and Exposition, Proceedings, 13 November 2009 through 19 November 2009 ; Volume 12, Issue PART A , 2010 , Pages 495-501 ; 9780791843857 (ISBN) Moeini, S. A ; Kahrobaiyan, M. H ; Rahaeifard, M ; Ahmadian, M. T ; Sharif University of Technology
    Abstract
    Atomic force microscopes (AFM) are widely used for feature detection and scanning surface topography of different materials. Contrast of topography images is significantly influenced by the sensitivity of AFM micro cantilever which means enhancement of sensitivity leads to increase of topography images resolution So, in the last years numerous scientists interested in studying the effects of different parameters such as geometric one on the sensitivity of AFM micro cantilevers. V-shape micro cantilever types of AFMs probe are widely used to scan various types of surfaces. In V-shape micro cantilevers, there are many geometric and design parameters which influence the flexural sensitivity of...