Browsing by Subject "Boundary integral equations"

Now showing 1 - 5 of 5

Open Access
Integral-equation study of ray effects and natural-mode resonances in a 2-D dielectric prism
(IEEE, 2015) Sukharevsky, İlya O.; Altıntaş, Ayhan
We analyze the interplay of two different types of electromagnetic behavior demonstrated by a 2-D dielectric prism: Geometrical Optics and resonance. As it is shown, the first is responsible, for instance, for enhanced reflection from an isosceles 90-degree prism of arbitrary epsilon and size, if illuminated from the base. The second is responsible for the peaks in the total scattering and absorption cross-sections (RCS) at the natural-mode frequencies. The numerical model is based on Nystrom discretization of Muller-type integral equations that provides guarantied convergence.
Open Access
Lens or resonator? Electromagnetic behavior of an extended hemielliptic lens for a sub-millimeter-wave receiver
(John Wiley & Sons, 2004) Boriskin, A. V.; Nosich, A. I.; Boriskina, S. V.; Benson, T. M.; Sewell, P.; Altintas, A.
The behavior of a 2D model of an extended hemielliptic silicon lens of a size typical for THz applications is accurately studied for the case of a plane E-wave illumination. The full-wave analysis of the scattering problem is based on the Mutter's boundary integral-equations (MB1E) that are uniquely solvable. A Calerkin discretization scheme with a trigonometric basis leads tu a very efficient numerical algorithm. The numerical results related to the focusability of the lens versus its rear-side extension and the angle of the plane-wave incidence, as well as near-field profiles, demonstrate strong resonances. Such effects can change the principles of optimal design of lens-based receivers.
Open Access
Manipulation of backscattering from a dielectric cylinder of triangular cross-section using the interplay of go-like ray effects and resonances
(Institute of Electrical and Electronics Engineers, 2015) Sukharevsky, Ilya O.; Nosich, A. I.; Altıtaş, Ayhan
A triangular dielectric cylinder (dielectric prism) of the size, in cross-section, comparable to or moderately larger than the wavelength is a scatterer, which blends together two different types of electromagnetic behavior: geometrical optics (GO) and resonance. As shown in this paper, the first is responsible, for instance, for enhanced reflection from an isosceles 90° prism, if illuminated from the base. The second is responsible for the peaks in the total scattering and absorption cross-sections (ACSs) at the natural-mode frequencies. The numerical analysis is performed by solving the well-conditioned Muller-type boundary integral equation (IE) discretized using an algorithm with controlled accuracy.
Open Access
Microcavity lasers on polymer materials: Boundary integral equation modeling and experiments
(IEEE, 2015-04) Nosich, A.I.; Smotrova, E.I.; Lebental, M.; Sukharevsky Ilya O.; Altıntaş, Ayhan
We consider the modeling and experiments with polymer dye-doped lasers shaped as thin flat cavities, allowing one to consider them as two-dimensional (2-D) active cavities. We focus our modeling on the H-polarized electromagnetic field in a kite-shaped laser. Assuming that the lasing-mode frequency is real-valued, we look for it together with the corresponding threshold value of material gain. Such electromagnetic-field problem is reduced to the Muller set of the boundary integral equations (MBIE), discretization of which yields determinantal equation. Numerical results reveal various types of modes existing in the kite including the perturbed whispering gallery (WG) modes that have the lowest thresholds. Their far-field emission patterns show good agreement with the measurements. © 2015 IEEE.
Open Access
Test of accuracy of the generalized boundary conditions in the scattering by thin dielectric strips
(IEEE, 2014-05) Nosich, A. I.; Shapoval, O. V.; Sukharevsky, Ilya O.; Altıntaş, Ayhan
The two-dimensional (2D) scattering of the E and H-polarized plane electromagnetic waves by a free-standing thinner than the wavelength dielectric strip is considered numerically. Two methods are compared: singular integral equations (SIE) on the strip median line obtained from the generalized boundary conditions for a thin dielectric layer and Muller boundary integral equations (BIE) for arbitrarily thick strip. The comparison shows the domain of acceptable accuracy of approximate model derived for thin dielectric strips. © 2014 IEEE.