Browsing by Keywords "Photonic crystal"
Now showing items 1-20 of 22
-
Absorption enhancement in InGaN-based photonic crystal-implemented solar cells
(SPIE, 2012-07-26)We investigate the absorption characteristics of InGaN solar cells with high indium (0.8) content and a one-dimensional periodic nano-scale pattern (implemented) in the InGaN layer theoretically. The short-circuit current ... -
AIBIIICVI 2 (A = Cu, Ag; B = Ga, In; C = S, Se, Te) based photonic crystal superlattices: optical properties
(Wiley-VCH Verlag, 2017)In this study, we present an investigation of the optical properties and band structures for the photonic structures based on AIBIIICVI 2 with a Fibonacci sequence that can act as a multi-wavelength birefringent filter. ... -
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 ... -
Dual-frequency division de-multiplexer based on cascaded photonic crystal waveguides
(Elsevier, 2012-02-28)A dual-frequency division de-multiplexing mechanism is demonstrated using cascaded photonic crystal waveguides with unequal waveguide widths. The de-multiplexing mechanism is based on the frequency shift of the waveguide ... -
Enhanced electro-optic modulation of LiNbO3-based photonic crystal cavities with dual mode and polarization operation
(TUBITAK, 2017)A high output transmission and high quality factor, compact LiNbO3 -based Fabry-Perot-type photonic crystal cavity is reported that can be used in electro-optical modulators at optical communication wavelengths. The ... -
Enhancing light extraction efficiency of InGaN/GaN multi quantum well light emitting diodes with embedded two dimensional photonic crystal structures
(Bilkent University, 2010-08)Advance in the growth methods of III-Nitrides and researches in order to eliminate doping problems of gallium nitride (GaN) resulted in high band gap materials with increased crystal quality which have led to tremendous ... -
Experimental demonstration of sub-wavelength imaging by left handed metamaterials
(2007)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 ... -
Highly directional enhanced radiation from sources embedded inside two and three-dimensional photonic crystals
(2005)In this work, we have experimentally and theoretically studied the emission of radiation from a monopole source embedded in a two and three dimensional photonic crystal. We have demonstrated the enhancement of radiation ... -
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 ... -
Multifrequency spatial filtering: a general property of two-dimensional photonic crystals
(Elsevier, 2016)Spatial filtering, an analog of frequency-domain filtering that can be obtained in the incidence angle domain at a fixed frequency is studied in the transmission mode for slabs of two-dimensional rod-type photonic crystals. ... -
Negative refraction and subwavelength focusing in two-dimensional photonic crystals
(Springer-Verlag, 2007)We experimentally and theoretically demonstrate negative refraction and focusing on electromagnetic (EM) waves by using two-dimensional photonic crystal slabs at microwave frequencies. Negative refraction is observed both ... -
Negative refraction and subwavelength focusing using photonic crystals
(2005)We review certain novel optical properties of two-dimensional dielectric photonic crystals (PCs) which exhibit negative refraction behavior. We investigate two mechanisms which utilize the band structure of the PC and lead ... -
One-way Rayleigh-Wood anomalies and tunable narrowband transmission in photonic crystal gratings with broken structural symmetry
(American Physical Society, 2013-05-03)In photonic crystal (PC) gratings whose structural symmetry is broken owing to one-side corrugations, the Rayleigh-Wood anomalies can appear in a one-way manner. In the combination with the vanishing coupling to the lowest ... -
Photonic band gap structures for WDM applications
(2002)A new structure by combining a single cavity and coupled-cavity waveguides (CCWs) for wavelength division multiplexing (WDM) applications was proposed. As such, a structure in which the coupling between the cavity mode and ... -
Photonic crystal-based resonant antenna with a very high directivity
(American Institute of Physics, 2000-09-24)We investigate the radiation properties of an antenna that was formed by a hybrid combination of a monopole radiation source and a cavity built around a dielectric layer-by-layer three-dimensional photonic crystal. We ... -
Physics and applications of defect structures in photonic crystals
(Springer, 2003)We propose and demonstrate a new type of propagation mechanism for electromagnetic waves in photonic band gap materials. Photons propagate through coupled cavities due to interaction between the highly localized neighboring ... -
Physics and applications of photonic crystals
(Nanotechnology Research Center NANOTAM, 2004)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 ... -
Physics and applications of photonic nanocrystals
(2004)Photonic nanocrystals are periodic dielectric or metallic structures having photonic bands in analogy to electronic bands of semiconductors. The presence of photonic band-gaps, where the propagation of photons of certain ... -
Physics and applications of photonic nanocrystals
(Inderscience Publishers, 2004)Photonic nanocrystals are periodic dielectric or metallic structures having photonic bands in analogy to electronic bands of semiconductors. The presence of photonic band-gaps, where the propagation of photons of certain ... -
A plain photonic crystal for generating directional radiation from embedded sources
(Institute of Physics Publishing Ltd., 2007)We investigate experimentally the generation of highly directional radiation from a plain two-dimensional photonic crystal structure where an embedded source couples to a photonic crystal band having Bloch modes of even ...
