Browsing by Author "Kafesaki, M."

Now showing items 1-11 of 11

    • Bilayer metamaterial: analysis of left-handed transmission and retrieval of effective medium parameters 

      Guven, K.; Cakmak, A. O.; Caliskan, M. D.; Gundogdu, T. F.; Kafesaki, M.; Soukoulis, C. M.; Özbay, Ekmel (Institute of Physics Publishing Ltd., 2007)
      We report an experimental and numerical analysis of a planar metamaterial designed for normal-to-plane propagation, and operating at microwave frequencies. The metamaterial consists of cutwire and wire patterns, which are ...

    • Chiral metamaterials with negative refractive index based on four "U" split ring resonators 

      Li, Z.; Zhao, R.; Koschny, T.; Kafesaki, M.; Alici, K. B.; Colak, E.; Caglayan, H.; Özbay, Ekmel; Soukoulis, C. M. (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 ...

    • Compact planar far-field superlens based on anisotropic left-handed metamaterials 

      Shen, N.-H.; Foteinopoulou, S.; Kafesaki, M.; Koschny, T.; Özbay, Ekmel; Economou, E. N.; Soukoulis, C. M. (American Physical Society, 2009-09-15)
      Pendry’s perfect lens has spurred intense interest for its practical realization at visible frequencies. However, fabrication of low-loss isotropic left-handed metamaterials is a current challenge. In this work, we ...

    • Composite chiral metamaterials with negative refractive index and high values of the figure of merit 

      Li, Z.; Caglayan, H.; Alici, K. B.; Kafesaki, M.; Soukoulis, C. M.; Özbay, Ekmel (Optical Society of America, 2012)
      A composite chiral metamaterial (CCMM) is designed and studied both numerically and experimentally. The CCMM is constructed by the combination of a continuous metallic wires structure and a purely chiral metamaterial (CMM) ...

    • Experimental demonstration of a left-handed metamaterial operating at 100 GHz 

      Gökkavas, M.; Güven, K.; Bulu, I.; Aydın, K.; Penciu, R. S.; Kafesaki, M.; Soukoulis, C. M.; Özbay, Ekmel (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 observasion of true left-handed transmission peaks in metamaterials 

      Aydin, K.; Guven, K.; Kafesaki, M.; Zhang, L.; Soukoulis, C. M.; Özbay, Ekmel (Optical Society of America, 2004-11-15)
      We report true left-handed (LH) behavior in a composite metamaterial consisting of a periodically arranged split ring resonator (SRR) and wire structures. We demonstrate the magnetic resonance of the SRR structure by ...

    • Investigation of magnetic resonances for different split-ring resonator parameters and designs 

      Aydin, K.; Bulu, I.; Guven, K.; Kafesaki, M.; Soukoulis, C. M.; Özbay, Ekmel (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 ...

    • Left-and right-handed transmission peaks near the magnetic resonance frequency in composite metamaterials 

      Katsarakis, N.; Koschny, T.; Kafesaki, M.; Economou, E. N.; Özbay, Ekmel; Soukoulis, C. M. (American Physical Society, 2004)
      We present free-space microwave measurements on composite metamaterials (CMMs) consisting of split ring resonators (SRRs) and wires either on the same dielectric board or on alternating boards. Our experimental results ...

    • Multi-gap individual and coupled split-ring resonator structures 

      Penciu, R.S.; Aydin, K.; Kafesaki, M.; Koschny Th.; Özbay, Ekmel; Economou, E.N.; Soukoulis, C.M. (Optical Society of American (OSA), 2008)
      We present a systematic numerical study, validated by accompanied experimental data, of individual and coupled split ring resonators (SRRs) of a single rectangular ring with one, two and four gaps. We discuss the behavior ...

    • Optically implemented broadband blueshift switch in the terahertz regime 

      Shen, N. H.; Massaouti, M.; Gokkavas, M.; Manceau J. M.; Özbay, Ekmel; Kafesaki, M.; Koschny, T.; Tzortzakis, S.; Soukoulis, C. M. (American Physical Society, 2011-01-18)
      We experimentally demonstrate, for the first time, an optically implemented blueshift tunable metamaterial in the terahertz (THz) regime. The design implies two potential resonance states, and the photoconductive semiconductor ...

    • Simulation and micro-fabrication of optically switchable split ring resonators 

      Gundogdu, T. F.; Gökkavas, M.; Güven, K.; Kafesaki, M.; Soukoulis, C. M.; Özbay, Ekmel (Elsevier BV, 2007-10)
      The effect of conductivity variation as a proposed method for the investigation of photoconductive switching properties of split ring resonators (SRRs) is simulated. Three different systems that are applicable under certain ...