Browsing by Keywords "Surface waves"
Now showing items 1-20 of 20
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Analysis of finite arrays of axially directed printed dipoles on electrically large circular cylinders
(IEEE, 2004)Various arrays consisting of finite number of printed dipoles on electrically large dielectric coated circular cylinders are investigated using a hybrid method of moments/Green's function technique in the spatial domain. ... -
Anisotropy sensitivity of an acoustic lens with slit aperture
(IEEE, 1993)A conventional spherical acoustic lens is modified by restricting its aperture in the form of a slit to provide directional sensitivity. The spacing between the two parallel absorbing sheets forming the slit is adjustable ... -
Characterization and imaging with lamb wave lens at gigahertz frequencies
(IEEE, 1994-10-11)Lamb wave lenses with conical refracting surfaces are fabricated for use at 400 MHz and 1 GHz. The conical surfaces are ground and polished with mechanical means and they are sufficiently smooth for the frequencies of ... -
Closed-form Green's functions for general sources and stratified media
(Institute of Electrical and Electronics Engineers, 1995-07)The closed-form Green's functions of the vector and scalar potentials in the spatial domain are presented for the sources of horizontal electric, magnetic, and vertical electric, magnetic dipoles embedded in general, ... -
Focusing surface waves using an axicon
(A I P Publishing, 1985-12)Axicons are generators of waves which focus on a line. They are used in various imaging and nondestructive testing applications as bulk wave focusing devices with a very long depth of focus. In this letter, a new type of ... -
Fresnel lamb wave and V-groove lenses with tunable mode selectivity
(IEEE, 1995)The Lamb wave and V-groove lenses are distinguished by their high surface wave excitation efficiencies. However, due to the fixed incidence angle, a particular lens can only be used for materials having surface wave ... -
Generation of focused surface waves with a solid wedge
(IEEE, 1987)Focusing of surface acoustic waves on material surfaces was achieved by axicons in liquid immersion. The system consisted of a plane acoustic wave generator obliquely insonifying a cylindrical mirror placed perpendicularly ... -
Imaging flaws close to surface using focused surface acoustic waves
(IEEE, 1986-11)The resolving power and detection ability of the focused surface acoustic wave (SAW) imaging modality is investigated in this paper. In this mode of imaging, conical bulk acoustic waves are used to generate and focus leaky ... -
Improving the accuracy of the surface integral equations for low-contrast dielectric scatterers
(IEEE, 2007)Solutions of scattering problems involving low-contrast dielectric objects are considered by employing surface integral equations. A stabilization procedure based on extracting the non-radiating part of the induced currents ... -
Iterative solution of the normal-equations form of the electric-field integral equation
(IEEE, 2007)In this paper, we show that transforming the original equations into normal equations improves the convergence of EFIE significantly. We present the solutions of EFIE by employing the least-squares QR (LSQR) algorithm, ... -
Long-range tamm surface plasmons supported by graphene-dielectric metamaterials
(American Institute of Physics Inc., 2017)Considering the Ohmic losses of graphene in the calculations and by obtaining exact dispersion relations of the modes, we theoretically study propagation and localization characteristics of Tamm surface plasmons supported ... -
Nearly perfect resonant absorption and coherent thermal emission by hBN-based photonic crystals
(Optical Society of America, 2017)In this paper, we numerically demonstrate mid-IR nearly perfect resonant absorption and coherent thermal emission for both polarizations and wide angular region using multilayer designs of unpatterned films of hexagonal ... -
Non-universal behavior of leaky surface waves in a one dimensional asymmetric plasmonic grating
(American Institute of Physics Inc., 2015)We report on a non-universal behavior of leaky surface plasmon waves on asymmetric (Si/Au/analyte of different height) 1D grating through numerical modelling. The occurrence of the leaky surface wave was maximized (suppressing ... -
Penetration depth of the scanning acoustic microscope
(IEEE, 1985-03)A definition for the penetration depth of the scanning reflection acoustic microscope is given. With this definition it is possible to calculate the penetration depth of a given lens geometry for a given material. The ... -
Response of surface acoustic wave imaging systems to cylindrical inhomogeneities
(IEEE, 1988-10)The authors present a theory to predict the response of a SAW (surface acoustic wave) imaging system. In particular, they calculate the response to cylindrical cavities as a function of cavity position with respect to the ... -
Surface wave splitter based on metallic gratings with sub-wavelength aperture
(Optical Society of American (OSA), 2008)We investigated the splitting of surface electromagnetic waves trapped at the output surface of a one-dimensional metallic grating structure. The output gratings of the structure asymmetrically such that the output surfaces ... -
A synthetic aperture imaging system using surface wave modes
(IEEE, 1995)A synthetic aperture acoustic imaging system with a novel inversion algorithm is described. Data is obtained by using a transducer insonifying the sample surface at a critical angle which is excited by a short electrical ... -
Use of a conical axicon as a surface acoustic wave focusing device
(IEEE, 1987-01)Ultrasonic axicons generate waves which focus on a line. They are used in various imaging applications as hulk wave focusing devices with a very long depth of focus. A new type of conical axicon is introduced. It consists ... -
V(Z) of the surface acoustic wave focusing system
(IEEE, 1986-11)It is possible to define a V(Z) function for the surface acoustic wave (SAW) focusing system for a class of reflectors similar to that defined in acoustic microscopy. In this case V(Z) is a function which relates the ... -
Wave propagation in metamaterial structures and retrieval of homogenization parameters
(Bilkent University, 2007)Electromagnetic wave propagation in metamaterial structures (metamaterial slabs, metamaterial cylinders, metamaterial coated conducting cylinders etc.) are investigated. Scattered and transmitted electromagnetic fields ...
