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Recent L-band radiometry from the SMOS and Aquarius satellite missions has sparked interest in studying low-frequency microwave-emission from the polar ice sheets [1, 2]. Low frequency microwaves have less extinction and extremely long penetration depth sin glacier ice (several hundreds to one thousand meters), and thus can provide sensitivity to the subsurface temperature profile. The Ultra-Wide...
Recently, we have developed the method of broadband Green's function with low wavenumber extraction (BBGFL) to investigate the problem of arbitrary shaped waveguides [1]. In the past, the Boundary Integral-the Resonant Mode Expansion (BIRME) [2, 3] method was applied to calculate the modes of an arbitrary shaped waveguide with a homogenous dielectric. In BIRME, a DC extraction is applied to remove...
Ultrashort laser interactions with dielectrics are numerically investigated by using a multi-physics approach based on Maxwell's equations coupled with a multiple rate free carrier density equation and with the integrated two-temperature model describing the energy transfer from the conduction band electrons to lattice. The model accounts for a complete Keldysh photoionization rate, impact ionization...
This paper addresses an accurate CAD oriented integrated closed-form model for the computation of losses for planar and non-planar slotline on a finite-thickness multilayered dielectric substrates. The analysis of the structures has been done using conformal mapping and single layer reduction (SLR) technique. The validity of the proposed integrated model is tested over wide range of parameters: 1...
The volume integral equation (VIE) formulations have been very accurate and efficient methods in modeling of inhomogeneous objects in electromagnetic areas. Over the years, various volume integral equation formations have been developed. In these formulations, the dielectric object is discretized into small sub-domains, such as tetrahedrons. Then basis functions are defined in each sub-domain and...
Results from numerical simulations to detect small dielectric inclusions surrounded by dielectric random scatterers have shown the feasibility of the MUltiple SIgnal Classification (MUSIC) algorithm, but further improvements must be made. In this paper, we consider the success of the multi-frequency MUSIC algorithm in detecting such inhomogeneities. Furthermore, we introduce the weighted multi-frequency...
We experimentally demonstrate the enhancement of the spontaneous emission rate of GaAs quantum wells (QWs) embedded in rolled-up metamaterials. We investigate the spontaneous emission lifetime of semiconductor QW heterostructures which are directly integrated inside rolled-up microtubes (RMTs) with hyperbolic dispersion. RMTs are prepared by self-rolling of strained metal-semiconductor layer systems...
Electromagnetic Inverse scattering problem has attracted vast attentions due to its wide application in geological exploration, security check, medical imaging and through wall imaging. The problem is commonly equivalent into a nonlinear optimization problem and regularization method is used to stabilize the ill-conditioned problem.
Plasmonic metamaterials, composed by arti?cial micro or nanostructures, exhibit extraordinary optical properties such as negative refraction, which cannot be observed in nature. The focused ion beam (FIB) and electron beam lithography (EBL) technique are frequently adopted to fabricate multilayer and three-dimensional plasmonic structures, but the alignment error, high cost and time consuming cannot...
In this paper, we applied the Born Iterative Method (BIM) to reconstruct three-dimensional inhomogeneous objects buried in spherically multilayered media. The nonlinear inverse problem is linearized by Born approximations and solved iteratively via the conjugate-gradient approach (CG). The forward scattering problem in the spherically multilayered media is solved by stabilized biconjugate-gradient...
Volume Integral Equations (VIEs) are indispensable for electromagnetic (EM) analysis by integral equation approach when inhomogeneous penetrable objects are involved. In the conventional method of moment (MoM) for solving the VIEs, unknown functions are expanded by a well-designed basis function like Schaubert-Wilton-Glisson (SWG) basis function, and a tedious testing procedure is required to transform...
Non-destructive testing of fiber-reinforced composite laminates as found, e.g., in airplanes, cars and for green energy applications, is challenging from academia to industry. Even if focusing onto electromagnetic testing (not by far the most common), a replete literature exists, encompassing low-frequency modalities tailored to graphite-fiber-based laminates [1] to less explored microwave ones when...
The tensor type data acquired by the triaxial induction tool enables the determination of not only resistivity, but also resistivity anisotropy of reservoir. The most popular anisotropic model for triaxial data interpretation is a horizontally layered formation with transversely isotropic (TI) resistivity anisotropy in each bed. When there is invasion developed in a permeable reservoir, the invasion...
Although Kirchhoff and subspace migration algorithms have been shown to be feasible for detecting various types of inhomogeneities, this has only been confirmed for cases where the inhomogeneities are located in a homogeneous medium. In this paper, we apply Kirchhoff and subspace migrations for the detection of small dielectric inhomogeneities enclosed by small randomly distributed dielectric scatterers...
In this talk, we present two experimental works on transformation optics and metamaterials in microwave frequency and electrostatics. The first is an experimental verification to an all-dielectric semi-spherical lens in the microwave regime, which exhibits extraordinary functions in shaping three-dimensional (3D) wave-propagation paths. On one hand, it was heuristically found that when radiation sources...
We present a survey of state-of-the-art segmentation methods that exploit partial differential equations, focusing on techniques introduced since the year 2010. The discussed approaches are mainly those based on the active contour and level set principles. The former of the two categories comprises methods utilizing parametric curve evolution based on the energy of the image function, and the resulting...
This paper presents the project of WLAN antenna made in microstrip technique working at a frequency of 5 GHz in 802.11ac IEEE standard. The paper presents the results of discussed numerical analysis.
A method to enhance microwave tomography through the use of an inhomogeneous background is proposed. Here, the measurement region is located in a circular perfect electrical conductor (PEC) chamber where known objects are placed inside the imaging domain as an inhomogeneous background. The Green function of a circular PEC chamber with inhomogeneous background is obtained using the method of moments...
In this talk I shall treat wave propagation through a very simple system: an isotropic slab of material that changes permittivity ε over its cross section (see Figure 1). I shall illustrate a method based on the application of complex spatial coordinates for designing inhomogeneous slabs that are invisible, or at least reflectionless from one side; connecting these scattering properties with the branch...
In this study, a potential biomaterial detection technology was successfully developed based on giant magnetoresistance (GMR) sensors. The GMR sensors were performed using [Co(1.5 nm)/Cu(x)]20 multilayer structures (x = 0.8, 0.9 and 1.0 nm) fabricated by DC magnetron sputtering. The X-ray diffraction (XRD) patterns showed that Co/Cu film multilayer has a high degree of crystallinity with a single...
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