2,816 research outputs found

    Transparent photonic band in metallodielectric nanostructures

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    Under certain conditions, a transparent photonic band can be designed into a one-dimensional metallodielectric nanofilm structure. Unlike conventional pass bands in photonic crystals, where the finite thickness of the structure affects the transmission of electromagnetic fields having frequency within the pass band, the properties of the transparent band are almost unaffected by the finite thickness of the structure. In other words, an incident field at a frequency within the transparent band exhibits 100% transmission independent of the number of periods of the structure. The transparent photonic band corresponds to excitation of pure eigenstate modes across the entire Bloch band in structures possessing mirror symmetry. The conditions to create these modes and thereby to lead to a totally transparent band phenomenon are discussed.Comment: To be published in Phys. Rev.

    Characteristics of bound modes in coupled dielectric waveguides containing negative index media

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    We investigate the characteristics of guided wave modes in planar coupled waveguides. In particular, we calculate the dispersion relations for TM modes in which one or both of the guiding layers consists of negative index media (NIM)-where the permittivity and permeability are both negative. We find that the Poynting vector within the NIM waveguide axis can change sign and magnitude, a feature that is reflected in the dispersion curves

    Local well-posedness and blow up in the energy space for a class of L2 critical dispersion generalized Benjamin-Ono equations

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    We consider a family of dispersion generalized Benjamin-Ono equations (dgBO) which are critical with respect to the L2 norm and interpolate between the critical modified (BO) equation and the critical generalized Korteweg-de Vries equation (gKdV). First, we prove local well-posedness in the energy space for these equations, extending results by Kenig, Ponce and Vega concerning the (gKdV) equations. Second, we address the blow up problem in the spirit of works of Martel and Merle on the critical (gKdV) equation, by studying rigidity properties of the (dgBO) flow in a neighborhood of solitons. We prove that when the model is close to critical (gKdV), solutions of negative energy close to solitons blow up in finite or infinite time in the energy space. The blow up proof requires in particular extensions to (dgBO) of monotonicity results for localized versions of L2 norms by pseudo-differential operator tools.Comment: Submitte

    Factors affecting the durability and wind resistance of asphalt shingles

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    An analysis of the alumni relations program of Heston College and Bible School.

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    Thesis (M.S.)--Boston Universit

    An analysis of wind losses to Iowa farm buildings

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    The Limitations on Voir Dire Examination of Jurors in Criminal Prosecutions

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    You : The American Woman

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    This publication discusses ways for women to make the most of their lives. It includes guidance on physical and mental health, physical fitness, fatigue, relaxation, and posture
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