Browsing by Author "Bulu, I."
Now showing items 1-20 of 34
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Beaming of electromagnetic waves emitted through a subwavelength annular aperture
(Optical Society of American (OSA), 2006)We study the diffraction of electromagnetic waves from subwavelength metallic circular apertures in the microwave spectrum. The theoretical and experimental demonstration of the near- and far-field electromagnetic distributions ... -
Beaming of light and enhanced transmission via surface modes of photonic crystals
(Optical Society of America, 2005-11-15)We report beaming and enhanced transmission of electromagnetic waves by use of surface corrugated photonic crystals. The modes of a finite-size photonic crystal composed of dielectric rods in free space have been analyzed ... -
Cavity formation in split ring resonators
(Elsevier BV, 2008-12)We report that it is possible to obtain a cavity structure by the deformation of a unit cell of an split ring resonator (SRR) structure. We presented the Q-factor of the cavity resonance as 192 for an SRR-based single ... -
Compact size highly directive antennas based on the SRR metamaterial medium
(Institute of Physics Publishing, 2005)In this work, we studied the far-field properties of the microwave radiation from sources embedded inside the split-ring resonator (SRR) metamaterial medium. Our results showed that the emitted power near the resonance ... -
Designing materials with desired electromagnetic properties
(Wiley, 2006)In this work, we suggest and demonstrate a robust method to tune the plasma frequencies of wire mediums. The method we suggest involves the use of two or more wire arrangements in the unit cell. By incorporating the method ... -
Electromagnetic wave focusing from sources inside a two-dimensional left-handed material superlens
(Institute of Physics Publishing, 2006)Lenses made of negative index materials exhibit different focusing behaviours compared to positive index material lenses. Flat lens behaviour and imaging below the diffraction limit is possible with negative refractive ... -
Enhanced transmission of microwave radiation in one-dimensional metallic gratings with subwavelength aperture
(American Institute of Physics, 2004)We report a theoretical and experimental demonstration of enhanced microwave transmission through subwavelength apertures in metallic structures with double-sided gratings. Three different types of aluminum gratings ... -
Experimental demonstration of a left-handed metamaterial operating at 100 GHz
(American Physical Society, 2006)The existence of a left-handed (LH) transmission band in a bulk composite metamaterial (CMM) around 100 GHz is demonstrated experimentally. The CMM consists of stacked planar glass layers on which periodic patterns of ... -
Experimental demonstration of labyrinth-based left-handed metamaterials
(Optical Society of America, 2005-12-12)In this present work, we propose and demonstrate a resonant structure that solves two major problems related to the split-ring resonator structure. One of the problems related to the split-ring resonator structure is the ... -
Experimental observation of subwavelength localization using metamaterial-based cavities
(Optical Society of America, 2009-01-01)We report subwavelength localization of electromagnetic fields within cavities based on metamaterials. Cavity resonances are observed in the transmission spectrum of a split-ring resonator and composite metamaterials cavity ... -
Extraordinary grating-coupled microwave transmission through a subwavelength annular aperture
(Optical Society of America, 2005-03-07)We studied coupling phenomena between surface plasmons and electromagnetic waves in the microwave spectrum using circular apertures surrounded by array of grooves. We first present experimental and theoretical results of ... -
Focusing of electromagnetic waves by a left-handed metamaterial flat lens
(Optical Society of America, 2005-10-31)We present here the experimental results from research conducted on negative refraction and focusing by a two-dimensional (2D) left-handed metamaterial (LHM) slab. By measuring the refracted electromagnetic (EM) waves from ... -
Focusing surface plasmons via changing the incident angle
(AIP Publishing LLC, 2008)We report a circular metallic aperture with a subwavelength circular slit in the microwave regime, in which we experimentally demonstrate that this aperture can excite and focus surface plasmons. Under normal illumination, ... -
Highly directional enhanced radiation from sources embedded inside three-dimensional photonic crystals
(Optical Society of America, 2005)We have experimentally studied emission of microwave radiation from a monopole source embedded in a three-dimensional photonic crystal. We have demonstrated enhancement of microwave radiation at the band edge and cavity ... -
Highly directive radiation and negative refraction using photonic crystals
(Institute of Physics Publishing, 2005)In this article, we present an experimental and numerical study of certain optical properties of two-dimensional dielectric photonic crystals (PCs). By modifying the band structure of a two-dimensional photonic crystal ... -
Highly directive radiation from sources embedded inside photonic crystals
(American Institute of Physics, 2003)In this work, we have experimentally and theoretically studied the angular distribution of power emitted from a radiation source embedded inside a photonic crystal. Our results show that it is possible to obtain highly ... -
Investigation of localized coupled-cavity modes in two-dimensional photonic bandgap structures
(IEEE, 2002)We present a detailed study of the localized coupled-cavity modes in 2-D dielectric photonic crystals. The transmission, phase, and delay time characteristics of the various coupled-cavity structures are measured and ... -
Investigation of magnetic resonances for different split-ring resonator parameters and designs
(Institute of Physics Publishing, 2005)We investigate the magnetic resonance of split-ring resonators (SRR) experimentally and numerically. The dependence of the geometrical parameters on the magnetic resonance frequency of SRR is studied. We further investigate ... -
Negative refraction and focusing of electromagnetic waves by metallodielectric photonic crystals
(American Physical Society, 2005)In this work, we have experimentally and theoretically studied negative refraction of electromagnetic waves by a metallodielectric photonic crystal. We showed that by adding a periodic dielectric perturbation to the unit ... -
Negative refraction, subwavelength focusing and beam formation by photonic crystals
(Institute of Physics Publishing Ltd., 2007)We present a review of our experimental and numerical studies on the negative refraction related phenomena in two-dimensional dielectric photonic crystals (PCs). By employing photonic bands with appropriate dispersion, the ...
