Now showing items 1-20 of 35

    • Acoustic cloaking transformations from attainable material properties 

      Ghezzo, F; Hunt, J; Smith, David R; Urzhumov, Yaroslav A (New Journal of Physics, 2010-07-12)
      We propose a general methodology and a set of practical recipes for the construction of ultra-broadband acoustic cloaks-structures that can render themselves and a concealed object undetectable by means of acoustic scattering. ...
    • Analysis of the power dependent tuning of a varactor-loaded metamaterial at microwave frequencies 

      Huang, D; Poutrina, E; Smith, David R (Applied Physics Letters, 2010-03-26)
      We present an analysis of the nonlinear, power-dependent resonance frequency shift for two metamaterial mediums consisting of arrays of varactor-loaded split ring resonators (VLSRRs). We confirm that, over a limited range ...
    • Analytic expressions for the constitutive parameters of magnetoelectric metamaterials 

      Smith, David R (Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 2010-03-17)
      Electromagnetic metamaterials are artificially structured media typically composed of arrays of resonant electromagnetic circuits, the dimension and spacing of which are considerably smaller than the free-space wavelengths ...
    • Broadband electromagnetic cloaking with smart metamaterials. 

      Baek, S; Choi, M; Jung, Y; Kang, G; Kim, K; Park, H; Shin, D; ... (9 authors) (Nat Commun, 2012)
      The ability to render objects invisible with a cloak that fits all objects and sizes is a long-standing goal for optical devices. Invisibility devices demonstrated so far typically comprise a rigid structure wrapped around ...
    • Characterization of high order modes of plasmonic antenna formed by nanoparticle/thin film hybrid structures 

      Chen, SY; Lazarides, Alexander; Smith, David R; Urzhumov, Yaroslav A (Proceedings of SPIE - The International Society for Optical Engineering, 2012-05-04)
      The plasmonic modes of a nano-antenna formed by a nanoparticle/thin film hybrid system are investigated. Plasmonic nano-antennas are well-known for their capabilities to concentrate electromagnetic wave into extreme small ...
    • Control of radiative processes using tunable plasmonic nanopatch antennas. 

      Ciracì, Dr Cristian; Hoang, TB; McGuire, F; Mikkelsen, MH; Mock, JJ; Rose, A; Smith, David R (Nano Lett, 2014-08-13)
      The radiative processes associated with fluorophores and other radiating systems can be profoundly modified by their interaction with nanoplasmonic structures. Extreme electromagnetic environments can be created in plasmonic ...
    • Controlling the second harmonic in a phase-matched negative-index metamaterial. 

      Huang, D; Rose, A; Smith, David R (Phys Rev Lett, 2011-08-05)
      Nonlinear metamaterials have been predicted to support new and exciting domains in the manipulation of light, including novel phase-matching schemes for wave mixing. Most notable is the so-called nonlinear-optical mirror, ...
    • Cross-section comparisons of cloaks designed by transformation optical and optical conformal mapping approaches 

      Kundtz, NB; Pendry, JB; Smith, David R; Urzhumov, Yaroslav A (Journal of Optics, 2011-02-01)
      We review several approaches to optical invisibility designed using transformation optics (TO) and optical conformal mapping (CM) techniques. TO is a general framework for solving inverse scattering problems based on mimicking ...
    • Designing three-dimensional transformation optical media using quasiconformal coordinate transformations. 

      Kundtz, N; Landy, Nathan I; Smith, David R (Phys Rev Lett, 2010-11-05)
      We introduce an approach to the design of three-dimensional transformation optical (TO) media based on a generalized quasiconformal mapping approach. The generalized quasiconformal TO (QCTO) approach enables the design of ...
    • Electronically reconfigurable metal-on-silicon metamaterial 

      Dhar, Sulochana; Jokerst, NM; Lee, JS; Nguyen, V; Schmalenberg, P; Smith, David R; Tyler, T; ... (8 authors) (Physical Review B - Condensed Matter and Materials Physics, 2012-08-08)
      Reconfigurable metamaterial-based apertures can play a unique role in both imaging and in beam-forming applications, where current technology relies mostly on the fabrication and integration of large detector or antenna ...
    • Enhancing imaging systems using transformation optics. 

      Kundtz, NB; Landy, Nathan I; Smith, David R; Urzhumov, Yaroslav A (Opt Express, 2010-09-27)
      We apply the transformation optical technique to modify or improve conventional refractive and gradient index optical imaging devices. In particular, when it is known that a detector will terminate the paths of rays over ...
    • Experimental determination of the quadratic nonlinear magnetic susceptibility of a varactor-loaded split ring resonator metamaterial 

      Huang, D; Larouche, S; Poutrina, E; Rose, A; Smith, David R (Applied Physics Letters, 2010-07-05)
      This letter presents a quantitative measurement of the second harmonic generated by a slab of varactor loaded split ring resonator metamaterial and the retrieval of the effective quadratic nonlinear magnetic susceptibility ...
    • Far-field analysis of axially symmetric three-dimensional directional cloaks. 

      Ciracì, Dr Cristian; Smith, David R; Urzhumov, Yaroslav A (Opt Express, 2013-04-22)
      Axisymmetric radiating and scattering structures whose rotational invariance is broken by non-axisymmetric excitations present an important class of problems in electromagnetics. For such problems, a cylindrical ...
    • Flow stabilization with active hydrodynamic cloaks 

      Smith, David R; Urzhumov, Yaroslav A (Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, 2012-11-21)
      We demonstrate that fluid flow cloaking solutions, based on active hydrodynamic metamaterials, exist for two-dimensional flows past a cylinder in a wide range of Reynolds numbers (Re's), up to approximately 200. Within the ...
    • Fluid flow control with transformation media. 

      Smith, David R; Urzhumov, Yaroslav A (Phys Rev Lett, 2011-08-12)
      We introduce a new concept for the manipulation of fluid flow around three-dimensional bodies. Inspired by transformation optics, the concept is based on a mathematical idea of coordinate transformations and physically ...
    • Going beyond Axisymmetry: 2.5D Vector Electromagnetics 

      Ciracì, Dr Cristian; Landy, Nathan I; Smith, David R; Urzhumov, Yaroslav A (2012-10)
      Linear wave propagation through inhomogeneous structures of size R≫λ (Fig.1) is a computationally challenging problem, in particular when using finite element methods, due to the steep increase of the number of degrees of ...
    • Gold nanoparticles on polarizable surfaces as Raman scattering antennas. 

      Chen, SY; Chilkoti, A; Hill, RT; Lazarides, Alexander; Mock, JJ; Smith, David R (ACS Nano, 2010-11-23)
      Surface plasmons supported by metal nanoparticles are perturbed by coupling to a surface that is polarizable. Coupling results in enhancement of near fields and may increase the scattering efficiency of radiative modes. ...
    • Isotropic-medium three-dimensional cloaks for acoustic and electromagnetic waves 

      Landy, Nathan I; Smith, David R; Urzhumov, Yaroslav A (Journal of Applied Physics, 2012-03-01)
      We propose a generalization of the two-dimensional eikonal-limit cloak derived from a conformal transformation to three dimensions. The proposed cloak is a spherical shell composed of only isotropic media; it operates in ...
    • Leveraging nanoscale plasmonic modes to achieve reproducible enhancement of light. 

      Chen, SY; Chilkoti, A; Hill, RT; Lazarides, Alexander; Mock, JJ; Oldenburg, SJ; Sebba, DS; ... (9 authors) (Nano Lett, 2010-10-13)
      The strongly enhanced and localized optical fields that occur within the gaps between metallic nanostructures can be leveraged for a wide range of functionality in nanophotonic and optical metamaterial applications. Here, ...
    • Low-loss directional cloaks without superluminal velocity or magnetic response. 

      Smith, David R; Urzhumov, Yaroslav A (Opt Lett, 2012-11-01)
      The possibility of making an optically large (many wavelengths in diameter) object appear invisible has been a subject of many recent studies. Exact invisibility scenarios for large (relative to the wavelength) objects involve ...