Enhanced transmission of slit arrays in an extremely thin metallic film

Horizontal resonances of slit arrays are studied. They can lead to an enhanced transmission that cannot be explained using the single-mode approximation. A new type of cavity resonance is found when the slits are narrow for a wavelength very close to the period. It can be excited for very low thicknesses. Optimization shows these structures could constitute interesting monochromatic filters

Whose Identity? An Argument for Granting Authority of Identity to the Individual

Who are you? And did you have any say in choosing who you are? Identity is a complicated issue, it is both individualistic and necessarily relies on your environment and peers. I believe that as it stands, your identity may be a result of both solitary and societal thinking. However, I think that society and government act as the sole authenticators of an individual’s identity. I do not believe this is how an individual’s life ought to be treated. Thus, I am arguing in this thesis that the individual has the capacity to choose their own identity, and that society and government ought to authenticate the decisions made by individuals. In order to prove my claim I will first specify the types of identity I will be discussing in this thesis. I will then explore the theories of three philosophers: Anthony Appiah, Ian Hacking, and Charles Taylor. In chapters 2 & 3, I will first analyze Anthony Appiah, who in arguing against the existence of race posits several ideas about identity including a theory of identity. Second, in chapter 4, I will analyze Ian Hacking, who presents a theory of identity creation, named labeling theory, and then presents a counter-theory of identity creation. Third, in chapter 5, I will analyze Charles Taylor’s claims about the effect recognition has on identity formation. Continuing to analyze Taylor in chapter 5, I will also analyze the importance of championing the politics of difference both to the individual and towards my claim. I will then provide examples of how my claim may be actualized in chapter 6, alongside counterarguments to my claims. Last, I will conclude my thesis in chapter 7

On the attenuation coefficient of monomode periodic waveguides

It is widely accepted that, on ensemble average, the transmission T of guided modes decays exponentially with the waveguide length L due to small imperfections, leading to the important figure of merit defined as the attenuation-rate coefficient alpha = -/L. In this letter, we evidence that the exponential-damping law is not valid in general for periodic monomode waveguides, especially as the group velocity decreases. This result that contradicts common beliefs and experimental practices aiming at measuring alpha is supported by a theoretical study of light transport in the limit of very small imperfections, and by numerical results obtained for two waveguide geometries that offer contrasted damping behaviours

Photon recycling in Fabry-Perot micro-cavities based on Si3_3N4_4 waveguides

We present a numerical analysis and preliminary experimental results on one-dimensional Fabry-Perot micro-cavities in Si$_3$N$_4$ waveguides. The Fabry-Perot micro-cavities are formed by two distributed Bragg reflectors separated by a straight portion of waveguide. The Bragg reflectors are composed by a few air slits produced within the Si$_3$N$_4$ waveguides. In order to increase the quality factor of the micro-cavities, we have minimized, with a multiparametric optimization tool, the insertion loss of the reflectors by varying the length of their first periods (those facing the cavity). To explain the simulation results the coupling of the fundamental waveguide mode with radiative modes in the Fabry-Perot micro-cavities is needed. This effect is described as a recycling of radiative modes in the waveguide. To support the modelling, preliminary experimental results of micro-cavities in Si$_3$N$_4$ waveguides realized with Focused Ion Beam technique are reported.Comment: 5 pages, 5 figure

Decomposing the scattered field of two-dimensional metaatoms into multipole contributions

We introduce a technique to decompose the scattered near field of two-dimensional arbitrary metaatoms into its multipole contributions. To this end we expand the scattered field upon plane wave illumination into cylindrical harmonics as known from Mie theory. By relating these cylin- drical harmonics to the field radiated by Cartesian multipoles, the contribution of the lowest order electric and magnetic multipoles can be identified. Revealing these multipoles is essential for the design of metamaterials because they largely determine the character of light propagation. In par- ticular, having this information at hand it is straightforward to distinguish between effects that result either from the arrangement of the metaatoms or from their particular design

Une machine à glace pour équipes mobiles d'immunisation

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Wide-angle reflection-mode spatial filtering and splitting with photonic crystal gratings and single-layer rod gratings

Cataloged from PDF version of article.New diffractive optical elements offering a frequency tolerant, very efficient, high-pass and bandpass spatial filtering over a broad range of incidence angles are demonstrated by numerical simulations. The device operates in reflection mode owing to the (nearly) perfect blazing. It relies on two-dimensional square-lattice photonic crystals composed of dielectric rods with simple corrugations at the interface. Similar performance can be obtained with gratings composed of a single rod layer placed in the near field of a metal mirror, indicating a route to geometries that can be easily fabricated with modern nanotechnologies. Also equal splitting between zero and first negative orders can be obtained for incidence-angle variations that are wider than 60 degrees. (C) 2014 Optical Society of Americ

Sharing the fruits of growth from 1950 to 2008: A surplus-accounting approach

In this paper, we apply the surplus accounting methodology to analyze the distribution of the fruits of growth between production factors over the period 1950-2008. Three production factors are distinguished: paid employment, self-employment and capital. The surplus distributed to capital is nil on average. The employees received a surplus linked to the evolution of total factor productivity, which experienced a slowdown in the 1980s Since 2007, the distributed surplus has sharply dropped, due to an increase in external deduction. The evolution of the surplus is, then, confronted to value-added distribution, by focusing on the capital-labour substitution in the 1980s. The standard framework of surplus accounting is, finally, extended by taking the Welfare System and its financing into account. Indeed, even if the Welfare System is mostly financed by social contributions paid by production factors, social benefits are also distributed to agents who are not involved in the production process, namely the pensioners, the unemployed, and the non-working population. We find that the surplus distributed to employees is lower when social contributions are taken into account. In the meantime, a half-percentage point of the value-added growth rate is assigned each year to the financing of the old-age insurance, whose main part however (0.4 point) accrues tothe growing number of new pensioners. Nevertheless, the incomes after social benefits allocated to the employed, the unemployed, and pensioners grow at a similar pace.Surplus Accounting, Value-Added Distribution, Welfare System, Pensioners

Minireview on Disordered Optical Metasurfaces

The use of coherent wave phenomena to enhance device performance is a cornerstone of modern optics. In juxtaposition to (locally) periodic metasurfaces, their disordered counterparts exhibit an interplay of destructive and constructive interferences occurring at the same spatial and spectral frequencies. This attribute provides disordered metasurfaces with a remarkable degree of flexibility, setting them apart from the constraints of periodic arrangements. Hereafter, we provide a concise overview of the cutting-edge developments and offer insights into the forthcoming research in this dynamic field