Search results for "Surface wave"
showing 10 items of 66 documents
Numerical study of surface waves generated by low frequency EM field for silicon refinement
2018
One of the most perspective methods to produce solar grade silicon is refinement via metallurgical route. The most critical part of this route is refinement from boron and phosphorus due to high segregation coefficients. One possible approach to remove boron is use of reactive gas on surface of silicon melt. An approach of creating surface waves on silicon melt's surface is proposed in order to enlarge its area and accelerate removal of boron via chemical reactions. This paper focuses on numerical analysis of surface wave creation by means of low frequency magnetic field. Frequency of magnetic field and its amplitude significantly change the character of surface waves with most changes occu…
Lagrangian finite element modelling of dam–fluid interaction: Accurate absorbing boundary conditions
2007
The dynamic dam-fluid interaction is considered via a Lagrangian approach, based on a fluid finite element (FE) model under the assumption of small displacement and inviscid fluid. The fluid domain is discretized by enhanced displacement-based finite elements, which can be considered an evolution of those derived from the pioneering works of Bathe and Hahn [Bathe KJ, Hahn WF. On transient analysis of fluid-structure system. Comp Struct 1979;10:383-93] and of Wilson and Khalvati [Wilson EL, Khalvati M. Finite element for the dynamic analysis of fluid-solid system. Int J Numer Methods Eng 1983;19:1657-68]. The irrotational condition for inviscid fluids is imposed by the penalty method and con…
Hybrid surface plasma modes in circular metal-coated tapered fibers
1999
The theory of hybrid surface plasma modes in metal-coated dielectric cylinders has been developed in recent years. We demonstrate that tapered fibers with a uniform waist and a circular metal coating can be designed for an efficient excitation of the fundamental hybrid surface plasma mode. Our experimental results are in good agreement with the theory and give the basis for the development of a novel type of all-fiber polarization-independent refractive-index sensor and tunable broadband wavelength filter.
Experimental Study of the Multipactor Effect in a Partially Dielectric-Loaded Rectangular Waveguide
2019
This letter presents the experimental study of the multipactor threshold in a partially dielectric-loaded rectangular waveguide, whose results validate a multipactor model recently developed by the authors, which includes the charge distribution appearing on the dielectric surface during the multipactor discharge. First, the variation of the multipactor RF voltage threshold has been theoretically analyzed in different waveguide configurations: in an empty waveguide, and also in the cases of a one-sided and two-sided dielectric-loaded waveguides. To reach this aim, an in-house Monte Carlo simulation tool has been developed. The Secondary Electron Yield (SEY) of the metallic and dielectric ma…
Analysis of Multipactor Effect in a Partially Dielectric-Loaded Rectangular Waveguide
2019
This paper 1 presents a study of the multipactor 2 effect in a partially dielectric-loaded rectangular waveguide. 3 To obtain the simulations presented in this paper, a detailed 4 analysis of the dynamics of the electron inside this waveguide 5 has been performed, taking into account the radio frequency 6 electromagnetic fields propagating in the waveguide and the dc 7 electric field that appears because of the charging of the dielectric 8 layer. This electrostatic field is obtained by computing the electric 9 potential produced by an arbitrary charge distribution on the 10 dielectric layer in a dielectric-loaded waveguide. The electron 11 trajectory is then found by numerically solving the…
Nonlocal dispersion anomalies of Dyakonov-like surface waves at hyperbolic media interfaces
2016
Dyakonov-like surface waves (DSWs) propagating obliquely on an anisotropic nanostructure have been theoretically proved in a few cases including 2D photonic crystals and metal-insulator (MI) layered metamaterials. Up to now, the long-wavelength approximation has been employed in order to obtain effective parameters to be introduced in the Dyakonov equation, which is largely restricted to material inhomogeneities of a few nanometers when including metallic elements. Here, we explore DSWs propagating obliquely at the interface between an insulator and a hyperbolic metamaterial, the latter consisting of a 1D MI bandgap grating using realistic slab sizes. We found unexpected favorable condition…
Surface waves in plasmonic anisotropie media
2012
We investigate the spatial dispersion of hybrid-polarized surface waves excited at the boundary of a semi-infinite layered metal-dielectric nanostructure. We put emphasis in the case that the thickness of a metal layer becomes of the order of the metal skin depth. We demonstrate that the use of the so-called effective medium approximation (EMA) is not justified, in general. For that purpose, we compare the results using the EMA model and numerical simulations based on the finite-element method. We include an analysis of the influence of metallic losses.
Quantitative subsurface defect detection in composite materials using a non-contact ultrasonic system
2002
The results of an experimental study conducted to detect subsurface defects in a thick Gr/PPS composite test sample using a noncontact ultrasonic system are presented. Surface waves are generated by a pulsed laser and detected by an air-coupled capacitance transducer. By controlling the surface wave wavelength through a shadow mask, it is possible to control surface wave penetration depth in the sample. Surface wave peak-to-peak amplitude is related to the near-surface material condition. Results indicate that signal amplitude decreases as the width of the defect increases and an approximately linear relation can be deduced.
Propagation of Dyakonon Wave-Packets at the Boundary of Metallodielectric Lattices
2013
We rigorously analyze the propagation of localized surface waves that takes place at the boundary between a semi-infinite layered metal-dielectric (MD) nanostructure cut normally to the layers and a isotropic medium. It is demonstrated that Dyakonov-like surface waves (also coined dyakonons) with hybrid polarization may propagate in a wide angular range. As a consequence, dyakonon-based wave-packets (DWPs) may feature sub-wavelength beamwidths. Due to the hyperbolic-dispersion regime in plasmonic crystals, supported DWPs are still in the canalization regime. The apparent quadratic beam spreading, however, is driven by dissipation effects in metal. This work was supported by the Spanish Mini…
Dark-and-bright rogue waves in long wave-short wave resonance
2014
Nonlinear Photonics, Bragg Gratings, Photosensitivity, and Poling in Glass Waveguides, in Proceedings Advanced Photonics, Part of Advanced Photonics, Barcelona, Spain, 28-31 July 2014