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  • NRN026 - Optimizing the Drude-Lorentz model for material permittivity: Method, program, and examples for gold, silver, and copper

    APS Physics

    • Sensors and Devices, 
    • Modelling

    Approximating the frequency dispersion of the permittivity of materials with simple analytical functions is of fundamental importance for understanding and modeling the optical response of materials and resulting structures. In the generalized Drude-Lorentz model, the permittivity is described in the complex frequency plane by a number of simple poles having complex weights, which is a physically relevant and mathematically simple approach: By construction, it respects causality, represents physical resonances of the material, and can be implemented easily in numerical simulations. We report here an efficient method of optimizing the fit of measured data with the Drude-Lorentz model having an arbitrary number of poles. We show examples of such optimizations for gold, silver, and copper, for different frequency ranges and up to four pairs of Lorentz poles taken into account. We also provide a program implementing the method for general use.

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  • NRN062 What the Deep Sea Can Tell Us About Microwaves

    27/05/2016

    • Sensors and Devices, 
    • Knowledge Transfer

    Background microwaves are ubiquitous in our modern, urban environment. The thermal effects of these electromagnetic fields on biological matter have been well-researched. However, possible non-thermal effects remain a controversial subject. Our work utilizes the bioluminescent marine organism, Vibrio fischeri, as a novel biosensor to probe the effects of low power, pulsed magnetic and electric 2.45 GHz microwave fields. The ultimate aim of this project is to microscopically image these biological effects in real-time using custom-made luminophores in mammalian cells, to elucidate the mode of action of microwaves at the molecular level.

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  • NRN039 In-Situ Synthesis of Magnetic Iron-Oxide Nanoparticle-Nanofibre Composites Using Electrospinning

    Science Direct

    • Sensors and Devices, 
    • Modelling

    We demonstrate a facile, one-step process to form polymer scaffolds composed of magnetic iron oxide nanoparticles (MNPs) contained within electrospun nano- and micro-fibres of two biocompatible polymers, Poly(ethylene oxide) (PEO) and Poly(vinyl pyrrolidone) (PVP).

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  • NRN045 External Optical Feedback Effects in Semiconductor Nanolasers

    IEEE Xplore

    • Sensors and Devices

    The response of nanolasers subject to external optical feedback has been analyzed. Calculations have been performed using rate equations, which include the Purcell cavity-enhanced spontaneous emission factor F and the spontaneous emission coupling factor β.

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  • NRN113 - Production of photonic nanojets by using pupil-masked 3D dielectric cuboid

    IOP Science

    • Sensors and Devices, 
    • Knowledge Transfer

    Photonic nanojets can be created via plane wave irradiation of multi-shaped mesoscale dielectric particles, and a waist of full-width at half-maximum (FWHM) smaller than the diffraction limit can be achieved in this process. In this paper, photonic nanojet produced by a pupil-masked 3D dielectric cuboid lens is numerically investigated under the irradiation of 532 nm wavelength plane wave. It is found that a pupil-masked cuboid lens is not only able to produce photonic nanojets with shorter FWHMs, but also increase its maximal intensity at certain masking ratios on the receiving surface. This phenomenon is different from the result of the spherical-lens reported in previous publications, and is attributed to the convergence of power flow and near-field numerical aperture (NA) increase after analysis of simulated power flow diagrams.

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