Browsing by Author "Bulu I."

Now showing 1 - 3 of 3

Open Access
Experimental observation of cavity formation in composite metamaterials
(Optical Society of American (OSA), 2008) Caglayan H.; Bulu I.; Loncar, M.; Özbay, Ekmel
In this paper, we investigated one of the promising applications of left-handed metamaterials: composite metamaterial based cavities. Four different cavity structures operating in the microwave regime were constructed, and we observed cavity modes on the transmission spectrum with different quality factors. The effective permittivity and permeability of the CMM structure and cavity structure were calculated by use of a retrieval procedure. Subsequently, in taking full advantage of the effective medium theory, we modeled CMM based cavities as one dimensional Fabry-Perot resonators with a subwavelength cavity at the center. We calculated the transmission from the Fabry-Perot resonator model using the one-dimensional transfer matrix method, which is in good agreement with the measured result. Finally, we investigated the Fabry-Perot resonance phase condition for a CMM based cavity, in which the condition was satisfied at the cavity frequency. Therefore, our results show that it is possible to treat metamaterial based cavities as one-dimensional Fabry-Perot resonators with a subwavelength cavity. © 2008 Optical Society of America.
Open Access
Physics and applications of photonic crystals
(Nanotechnology Research Center NANOTAM, 2004) Özbay, Ekmel; Bulu I.; Aydin, K.; Caglayan H.; Guven, K.
In this article, we investigate how the photonic band gaps and the variety of band dispersions of photonic crystals can be utilized for various applications and how they further give rise to completely novel optical phenomena. The enhancement of spontaneous emission through coupled cavity waveguides in a one-dimensional silicon nitride photonic microcrystal is investigated. We then present the highly directive radiation from sources embedded in two-dimensional photonic crystals. The manifestation of novel and intriguing optical properties of photonic crystals are exemplified experimentally by the negative refraction and the focusing of electromagnetic waves through a photonic crystal slab with subwavelength resolution. © 2004 Elsevier B.V. All rights reserved.
Open Access
Transmission properties of various split-ring resonator systems
(Optical Society of America, 2006) Aydın, Koray; Bulu I.; Güven, K.; Özbay, Ekmel
We investigated the magnetic resonance of split-ring resonators (SRR) experimentally. The dependence of the geometrical parameters on the resonance frequency of SRR is studied. We further investigated the effect of disorder on performance of SRRs. © 2006 Optical Society of America.