Browsing by Keywords "Metamaterials"
Now showing items 1-20 of 90
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Accurate modeling of metamaterials with MLFMA
(2006)Electromagnetic modelling of large metamaterial (MM) structures employing multilevel fast multipole algorithm (MLFMA) is reported. MMs are usually constructed by periodically embedding unit cells, such as split-ring ... -
All-silicon ultra-broadband infrared light absorbers
(Nature Publishing Group, 2016)Absorbing infrared radiation efficiently is important for critical applications such as thermal imaging and infrared spectroscopy. Common infrared absorbing materials are not standard in Si VLSI technology. We demonstrate ... -
Analysis of double-negative materials with surface integral equations and the multilevel fast multipole algorithm
(2011)We present a fast and accurate analysis of double-negative materials (DNMs) with surface integral equations and the multilevel fast multipole algorithm (MLFMA). DNMs are commonly used as simplified models of metamaterials ... -
Asymmetric chiral metamaterial circular polarizer based on four U-shaped split ring resonators
(Optical Society of America, 2011-04-28)An asymmetric chiral metamaterial structure is constructed by using four double-layered U-shaped split ring resonators, which are each rotated by 90° with respect to their neighbors. The peculiarity of the suggested design ... -
AVBVICVII ferroelectrics as novel materials for phononic crystals
(Taylor and Francis Inc., 2017)In the present work the acoustic band structure of a two-dimensional (2D) phononic crystal (PC) containing a semiconducting ferroelectric - AVBVICVII (A = Sb, Bi; B = S, Se, Te; C = I, Br, and Cl) was investigated theoretically ... -
Beaming and enhanced transmission through a subwavelength aperture via epsilon-near-zero media
(Nature Publishing Group, 2017)We numerically validate and experimentally realize considerable funneling of electromagnetic energy through a subwavelength aperture that is covered with an epsilon-near-zero metamaterial (ENZ). The epsilon-near-zero ... -
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 ... -
Chiral metamaterials with negative refractive index based on four "U" split ring resonators
(American Institute of Physics, 2010-08-23)A uniaxial chiral metamaterial is constructed by double-layered four "U" split ring resonators mutually twisted by 90°. It shows a giant optical activity and circular dichroism. The retrieval results reveal that a negative ... -
Chiral metamaterials: From negative index to asymmetric transmission
(2013)Chiral metamaterials are attractive for their intriguing properties such as negative refractive index, optical activity and circular dichroism, and asymmetric transmission. In this paper, we review the research we have ... -
Chiral Structures: Manipulation of Asymmetric Transmission in Planar Chiral Nanostructures by Anisotropic Loss (Advanced Optical Materials 7/2013)
(2013)Asymmetric transmissions of circularly polarized optical waves can be achieved when the waves are incident normal to planar chiral structures, provided that the structures are anisotropic and lossy. In order to clarify how ... -
Compact left-handed metamaterial based on double-layer planar metal strip arrays
(Optical Society of America, 2006)The existence of a left-handed transmission peak of a metamaterial consisting of double-layer planar metal strip arrays at 15 GHz is demonstrated. This design is very suitable to submicron scales required at communication ... -
Computational analysis of complicated metamaterial structures using MLFMA and nested preconditioners
(2007)We consider accurate solution of scattering problems involving complicated metamaterial (MM) structures consisting of thin wires and split-ring resonators. The scattering problems are formulated by the electric-field ... -
Continuously tunable terahertz metamaterial employing magnetically actuated cantilevers
(Optical Society of American (OSA), 2011)Terahertz metamaterial structures that employ flexing microelectromechanical cantilevers for tuning the resonance frequency of an electric split-ring resonator are presented. The tuning cantilevers are coated with a magnetic ... -
Conversion from constitutive parameters to dispersive transmission line parameters for multi-band metamaterials
(Taylor and Francis Ltd., 2016)In this study, we explain an approach including conversion from constitutive parameters to dispersive transmission line parameters using the double-band DNG (double-negative) properties of the circular type fishnet ... -
Design of compact optical devices based on periodic meta-structures
(Bilkent University, 2013)Manipulation of the flow of light is demanded for several applications such as communication, data storage, sensor, photovoltaic cells, microscopy, lasers and light emitting diodes for the purpose of designing compact, ... -
Design of miniaturized narrowband absorbers based on resonant-magnetic inclusions
(IEEE, 2011-06-21)In this paper, we present the design of miniaturized narrowband-microwave absorbers based on different kinds of magnetic inclusions. The operation of the proposed components originates from the resonance of a planar array ... -
Design of novel printed microwave band-reject filters using split-ring resonator and complementary split-ring resonator
(Bilkent University, 2008)Filters are one of the fundamental microwave components used to prevent the transmission or emission of signals with unwanted frequency components. In general, they can be considered as an interconnection of resonator ... -
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 ... -
Determining the effective constitutive parameters of finite periodic structures: Photonic crystals and metamaterials
(Institute of Electrical and Electronics Engineers, 2008)A novel approach to find the effective electric and magnetic parameters of finite periodic structures is proposed. The method uses the reflection coefficients at the interface between a homogenous half-space and the periodic ... -
Development of left-handed composite materials and negative refracting photonic crystals with subwavelength focusing
(2005)We review the studies conducted in our group concerning electromagnetic properties of metamaterials and photonic crystals with negative effective index of refraction. In particular, we demonstate the true left handed ...
