Wyniki wyszukiwania - BazTech

1

Basic Logic Gates in Two Dimensional Photonic Crystals for All Optical Device Design

Sonth Mahesh V, Srikanth Gimmadi, Agrawal Pankaj, Premalatha B.

International Journal of Electronics and Telecommunications

|

2021

|

Vol. 67, No. 2

247--261

EN

The research carried out in the field of optics and photonics with an idea to design and develop the all optical logic devices in the fascinating material known as photonic crystals (PhCs). The structural investigation reveals that the two dimensional (2-D) PhCs is more suitable for fabrication of optoelectronic components. In this article we have designed basic logic gates in 2-D PhCs as they are the building blocks for the construction of optical devices and in these, refractive index is periodically modulated with the wavelength. The understanding of light behaviour in complex PhCs helps in creating photonic band gap (PBG) that can prevent light of certain wavelength propagating in crystal lattice structure. For the selected geometry structure, three PBG bands will exists out of which two of them are transverse electric (TE) and one is transverse magnetic (TM) mode. The PBG bands in the TE mode ranges from 0.31( α λ ) to 0.46( α λ ), 0.61( α λ ) to 0.63( α λ ) and TM mode ranges from 0.86( α λ ) to 0.93( α λ ). The free space wavelength of 1550 nm is set for the finite difference time domain (FDTD) simulation of the structure. The response time and computational overhead required for the proposed OR gate is 0.128ps and 4.4MB is obtained. Also we calculated the extinction ratio for AND gate and NOT gate as 6.19 dB and 10.21 dB respectively.

2

Telecommunication filter based on the symmetrical photonic crystal Bg5/Cu1/Bg5

Baraket Z., Zaghdoudi J., Kanzari M.

Optica Applicata

|

2018

|

Vol. 48, nr 3

361--371

EN

Thanks to the transfer matrix method, we perform a theoretical investigation of the optical properties of the symmetrical photonic crystal designed as Bg5/Cu1/Bg5, where Cu1 is the first generation of the copper mean sequence and Bg5 is the fifth generation of the Bragg sequence. We design a developed polychromatic filter which allows the transmission of all the telecommunication wavelengths 0.85, 1.3, and 1.55 µm at oblique incidence for both of TE and TM polarization with a high transmission rate and high quality factor. This photonic crystal can be employed in the fabrication of telecommunication devices.

3

Design of a novel photonic crystal 1.31/1.55 µm bi-band filter for near infrared application

Lallam F., Badaoui H., Abri M., Fedaouche A.

Optica Applicata

|

2018

|

Vol. 48, nr 3

341--348

EN

A novel design of a double selective filter for integrated optics in two-dimensional photonic crystals operating at a wavelength of 1.31 and 1.55 µm is proposed in this paper. We focus particularly on filters transmission and selectivity enhancement. The two-dimensional photonic crystals filters are simulated by using a combination of three cascaded waveguides; these later are conceived by one missing row and with different rods radii for efficient filtering purpose. The properties of these photonic crystal structures are numerically investigated by using the two-dimensional finite-difference time-domain method and the numerical results are given for incident light wave having transverse electrical polarization. A final synthesized filter topology is presented and the maximum of transmission is found around 70% and 60% localized respectively near 1.31 and 1.55 µm wavelengths.

4

Defect modes properties in one-dimensional photonic crystals employing a superconducting nanocomposite material

Aly A. H., Elsayed H. A., Malek C.

Optica Applicata

|

2018

|

Vol. 48, nr 1

53--64

EN

In the present work, we investigate theoretically the transmission characteristics of one-dimensional photonic crystals that contain a defect layer of a nanocomposite material in infrared radiation. The theoretical treatment is obtained depending on the fundamentals of the characteristic matrix method. Here, the nanocomposite designed from nanoparticles of a superconducting material is arranged into a dielectric medium. The numerical results clarify the acute effect of the volume fraction and the operating temperature on the effective permittivity of the nanocomposite material. Therefore, the volume fraction, the operating temperature and other parameters such as the permittivity of the dielectric material and the threshold frequency could have a significant effect on the characteristics of the defect modes. Thus, our structure may be very promising in many applications such as narrow band filters and among optoelectronic applications.

5

Computer simulation and modeling of solar energy based on photonic band gap materials

Aly A. H., Sayed H.

Optica Applicata

|

2018

|

Vol. 48, nr 1

117--126

EN

In this paper, we have obtained theoretically a convenient way to improve the tandem solar cell efficiency by using one-dimensional binary photonic crystals in the anti-reflection coating and intermediate reflective layer. Also, we design and simulate our structure by using two different methods; MATLAB program based on a transfer matrix method and COMSOL Multiphysics software based on a finite element method. We have obtained the localization of the photons energy on the appropriate cell and then reduced the energy losses by controlling the photonic band gap. The present design is more convenient for cold countries.

6

The effect of the symmetrical deformation y = xk + 1 on the optimization of the symmetrical multiple channeled white light color filter

Baraket Z., Zaghdoudi J., Kanzari M.

Optica Applicata

|

2017

|

Vol. 47, nr 1

19--28

EN

In this paper, we consider a hybrid photonic crystal symmetrically deformed (Bg5/Cu3/Bg5) consisting of the third generation of the copper mean sequence (Cu3), sandwiched between two Bragg mirrors at the fifth generation (Bg5). Our system realizes a polychromatic filter that transmits five wavelengths in the visible spectrum independently of the polarization of the light transverse electric or transverse magnetic. Secondly, the photonic crystal (Bg5/Cu3/Bg5) undergoes the deformation y = xk + 1 (where k is the degree of deformation, x and y are respectively the coordinates of the system before and after the deformation). With a proper choice of the degree of deformation k, this photonic crystal maintains its property of polychromatic filter whose transmission wavelength is independent of the polarization’s state. Thanks to this deformation, we can disperse the optical windows in different spectra of visible light and exactly in the violet, blue, green, and orange light. This system can be used in the fabrication of color filter devices and the white light emitting diodes.

7

Modeling of thermal tunable multichannel filter using defective metallic photonic crystals

Gharaati A., Zare Z.

Optica Applicata

|

2017

|

Vol. 47, nr 4

611--619

EN

The transmission spectra of one dimensional metallic photonic crystal containing defects are studied using a transfer matrix method. We consider silver as a defect layer with a refractive index dependent on wavelength and temperature simultaneously. Since the loss factor of silver is the function of temperature, we should find a structure that has sharp transmission peaks to model a filter. We present the structure with a coupled defect. It is found that the number of transmission resonant peaks is equal to the number of coupled defects and they are tunable with temperature and incident angle.

8

A Photonic-Crystal Selective Filter

Pajewski L., Schettini G.

Journal of Telecommunications and Information Technology

|

2017

|

nr 3

107--112

EN

A highly selective filter is designed, working at 1.55 μm and having a 3-dB bandwidth narrower than 0.4 nm, as is required in Dense Wavelength Division Multiplexed systems. Different solutions are proposed, involving photonic crystals made rectangular- or circular-section dielectric rods, or else of holes drilled in a dielectric bulk. The polarization and frequency selective properties are achieved by introducing a defect in the periodic structure. The device is studied by using in-house codes implementing the full-wave Fourier Modal Method. Practical guidelines about advantages and limits of the investigated solutions are given.

9

Diody elektroluminescencyjne na bazie GaN z powierzchniowymi kryształami fotonicznymi

Gołaszewska K., Kruszka R., Myśliwiec M., Ekielski M., Jung W., Piotrowski T., Juchniewicz M., Bar J., Wzorek M., Kamińska E., Piotrowska A., Sarzała R. P., Dems M., Wojtas J., Mędrzycki R., Prystawko P.

Elektronika : konstrukcje, technologie, zastosowania

|

2013

|

Vol. 54, nr 9

46-49

PL

W artykule omówiono proces technologiczny wytwarzania diody elektroluminescencyjnej Al(In)GaN/GaN o emisji promieniowania w zakresie 380…400 nm z maksimum dla 384 nm oraz dostosowanych do niej kryształów fotonicznych. Zastosowanie kryształu fotonicznego w formie współśrodkowych pierścieni o stałej sieci 3 μm i wypełnieniu 60% wytrawionych w strukturze DEL pozwoliło na ponad dwukrotny wzrost mocy promieniowania, ograniczenie stożka emisji ze 150 do 90° oraz uzyskanie pojedynczego maksimum emisji w kierunku normalnym do powierzchni diody.

EN

This communication describes the fabrication of an Al(In)GaN/GaN light emitting diode (LED) emitting in the range 380...400 um with a maximum at 384 um along with the fabrication of appropriate photonic crystals. The etching of photonic crystals with a concentric ring structure with a 3 μm lattice constant and 60% filling factor in the LED structure yielded a more than doubled radiation power, more focused radiation cone of 90 instead of the initial 150° and a single energy maximum normal to the LED surface.

10

One-to-three and T-shaped beam splitters based on self-collimating photonic crystals

Wu Z, Xie K, Yang H, He X

Optica Applicata

|

2012

|

Vol. 42, nr 4

845--852

EN

In this paper, a one-to-three beam splitter and a T-shaped one-to-two beam splitter are proposed by introducing a V-shaped air gap into a self-collimating photonic crystal (PC). By adjusting the width of the introduced air gap to proper values, the incident beam can be divided into two or three sub-beams. The plane wave expansion method is employed to obtain the equifrequency contours and the band diagram of the PC. The splitting ratios between the sub-beams as a function of the width of the air gap are calculated by using the finite-difference time-domain method. Meanwhile, the field distributions of the light propagation in the structure are presented.

11

Dwuwymiarowe kryształy fotoniczne jako materiał nowoczesnej fotoniki : metody wytwarzania i zastosowania

Lis S., Ptasiński K., Ryba P., Wielichowski M., Zakrzewski A., Patela S.

Elektronika : konstrukcje, technologie, zastosowania

|

2012

|

Vol. 53, nr 2

29-32

PL

Kryształy fotoniczne to sztucznie wytwarzane struktury, które mogą pełnić rolę materiału bazowego do budowy elementów fotoniki. W pracy omówiono jedną z metod wytwarzania kryształów fotonicznych - tak zwaną litografię interferencyjną. Następnie przeanalizowano możliwość wykorzystania struktur kryształu fotonicznego do budowy optycznego czujnika gazów.

EN

Photonic crystal is an artificially fabricated structure, that can serve as a base material for production of photonic elements. In this paper one of the methods of photonic crystal fabrication - so called interference lithography - is presented. Further, possibility of application of the photonic crystal for design of optical gas sensor is analyzed.

12

GaAs/AlGaAs photonic crystals for VCSEL-type semiconductor lasers

Kruszka R., Ekielski M., Gołaszewska K., Korwin-Mikke K., Sidor Z., Wzorek M., Pierścińska D., Sarzała R., Czyszanowski T., Piotrowska A.

Opto-Electronics Review

|

2011

|

Vol. 19, No. 1

51-55

EN

The results of modelling of the influence of photonic crystal on the performance of VCSEL-type semiconductor laser structure are shown and indicate that the use of those structures would significantly improve the working parameters of the devices. The method of fabrication of photonic crystals in the Bragg mirrors of GaAs/AlGaAs-based VCSELs is presented.

13

Broad angle and frequency tunable photonic crystal-polarization beam splitter based on negative refraction: Transition from right-handed to left-handed medium

Rajput M., Sinha R. K.

Optica Applicata

|

2011

|

Vol. 41, nr 1

29--40

EN

A new design of a broad angle photonic crystal polarization beam splitter (PhC-PBS) with frequency tunable index of refraction, i.e. varying from positive to negative, is presented. Designed PhC-PBS shows transition from right-handed medium (positive index medium) to left-handed medium (negative index medium) with change in normalized frequency from 0.437 to 0.516. The design description includes band structure calculations and equi-frequency contour (EFC) analysis, where direction of refraction is tuned by the frequency and thickness of a slab. The proposed PBS splits transverse electric (TE) polarization in negative direction and transverse magnetic (TM) polarization in positive direction for optical communication windows in the range of 1.31 žm and 1.55 žm. Finite difference time domain (FDTD) method is employed to evaluate left-handed, right-handed transmission and reflection characteristics. High transmission and extinction ratio at wide range of incident angles validate proposed design as an efficient and broad angle PBS based on tunable negative refraction. Demonstration of near- and far-field resonance patterns reveals that proposed structure has the high potential in the design and development of the multiple photonic device applications, i.e., highly directional optical antennas also.

14

Propagacja fali elektromagnetycznej w falowodzie wykonanym w planarnym krysztale fotonicznym do zastosowań w diodzie o emisji krawędziowej

Dems M.

Elektronika : konstrukcje, technologie, zastosowania

|

2011

|

Vol. 52, nr 9

40-42

PL

W artykule zaprezentowano zastosowanie metody admitancyjnej fal płaskich do modelowania propagacji światła w planarnym falowodzie opartym na krysztale fotonicznym. Przedstawiono także analizę falowodu wielomodowego w którym następuje znaczne zwiększenie strat optycznych spowodowane sprzęganiem poszczególnych modów oraz towarzyszące temu zjawisku powstawanie mini-przerwy fotonicznej. W niniejszej pracy pokazano, że przerwa taka może zaniknąć, jeżeli uwzględniona zostanie możliwość stratnej propagacji światła w falowodzie. Wyniki te są istotne dla zrozumienia fizyki falowodów opartych na kryształach fotonicznych, które są istotnymi elementami w diodach LED o emisji krawędziowej.

EN

This work presents the application of the plane-wave admittance method to modeling the propagation of light in a photonic crystal waveguide. Furthermore, a multi-mode waveguide is analyzed and the increase of losses due to the mode coupling is determined. As such mode coupling introduces a photonic mini stop band, its formation is analyzed. It is found that such a mini stop band can disappear when the complex propagation constant is allowed The results give a new insight into the physics of photonic-crystal waveguides. which are of high importance in edge-emitting LEDs.

15

Nonlinearity-controllable all-optical logic gates based on broadband defect mode

Liu B., Tian H., Lu H., Ji Y.

Optica Applicata

|

2010

|

Vol. 40, nr 3

657--668

EN

To avoid the adverse effect of unstable nonlinear progress on the design of all-optical logic gates, the broadband defect mode of one-dimensional photonic crystal with dual-defects has been studied. By using transfer matrix method, influences of period number and refractive indices on crystal’s transmission spectrum are analyzed. It is pointed out that with proper parameters, broadband defect mode, which could be used to reduce the influence between the nonlinear refractive index and field distribution, can be gained. Due to this fact, the designed XOR, AND and NOT logic gates can be steadily controlled with low-threshold and high-contrast.

16

Interferential polychromatic filters based on the quasi-periodic one-dimensional generalized multilayer Thue - Morse structures

Bouazzi Y., Kanzari M.

Optica Applicata

|

2009

|

Vol. 39, nr 3

489-498

EN

In this paper, a new type of optical filter using photonic band gap materials has been proposed. The optical filter was obtained by a combination of periodic H(LH)J and generalized Thue - Morse (GTM) quasi-periodic one-dimensional multilayer. We show that the whole structure H(LH)J[TM]PH(LH)J, where P is the repetition number of the GTM stack, has an interesting application as a polychromatic filter. However, the effect of the repetition number for producing an improved polychromatic filter is presented. So, switches like (on-on-off-off-on-on-…) have been found.

17

Fabrication of photonic crystal structures by laser lithography

Mizeikis V., Seet K. K., Juodkazis S., Misawa H.

Journal of Automation Mobile Robotics and Intelligent Systems

|

2009

|

Vol. 3, No. 4

99-101

EN

Using femtosecond laser lithography technique, we have fabricated 3D PhC structures having woodpile and spiral architectures in photoresists, and investigated their photonic properties. The fabricated structures exhibit good structural quality, evidenced by long-range periodicity and absence of deformations, and photonic stop-gaps at nearinfrared and infrared wavelengths, evidenced by spectral bands of high reflectivity. These structures can be used as templates for further enhancement by infiltration of metals or high refractive index materials, such as Si.

18

Electromagnetic FDTD modeling of optical problems

Salski B., Gwarek W., Celuch M.

Elektronika : konstrukcje, technologie, zastosowania

|

2009

|

Vol. 50, nr 4

53-55

EN

This paper presents a review of state-of-the-art electromagnetic modeling of optical problems with the Finite-Difference Time-Domain (FDTD) method. It addresses theoretical and practical issues referring to photonic crystals (PhC) that are of great interest in optics nowadays. Computational examples are introduced to show a possible scope of applications of PhC. Our aim is to demonstrate this dynamically developing branch of science that pushes FDTD modeling forvard into higher frequencies, far beyond the original applications in microwaves.

PL

Artykuł prezentuje przegląd zastosowań metody różnic skończonych w dziedzinie czasu (ang. FDTD) do modelowania elektromagnetycznego zagadnień optycznych. Omawiane są teoretyczne i praktyczne problemy istotne w projektowaniu kryształów fotonicznych (ang. PhC), które cieszą się obecnie wielkim zainteresowaniem. Wprowadzone przykłady obliczeniowe ukazują szeroki zakres zastosowań kryształów fotonicznych w optyce. Celem autorów jest zaprezentowanie tej dynamicznie rozwijającej się dziedziny naukowej, która otwiera nowe możliwości dla modelowania elektromagnetycznego metodą FDTD w zakresie częstotliwości znacznie wykraczającym poza technikę mikrofalową.

19

Guided modes in capillary optical fibers

Romaniuk R. S.

Electronics and Telecommunications Quarterly

|

2008

|

Vol. 54, No 3

323-342

EN

A comparatively large group of capillary optical fibers, referred to in this paper as COF, consists of several families of optical filaments. The basic division line goes through the wave guidance mechanism. Two basic kinds of capillary optical fibers are of refractive and photonic mechanism of guided wave transmission. The work tries to compare wave modes in both kinds of optical fiber capillaries: refractive (RCOF) and photonic (PCOF). The differences are emphasized indicating prospective application areas of these fibers. Refractive COF carries most of the modal light in the ring-like, high-refraction, optical glass core encircling an empty capillary hole. Refractive capillary optical fibers are used widely for photonic instrumentation applications, due to the proximity of optical wave and capillary hole with the evanescent wave. The hole can be filled with a material subject to optical guided wave spectrometry. Photonic COF carries most of the light in air (or vacuum). Thus, photonic capillary optical fibers are considered for trunk optical communications, with guided wave travelling in vacuum rather than in glass - avoiding in this way the Rayleigh scattering. The fundamental mode in a refractive COF is LPoi or dark hollow beam (DHB) of light with zero intensity on fiber axis. The fundamental mode in a photonic COF is Gaussian beam with maximum intensity on fiber axis. The photonic COFs can be further divided to two basic groups: porous or holey/hollow and Bragg or OmniGuide fibers. These two kinds of PCOFs differ by the method of building a photonic band gap (PBG) around a capillary hole. The paper is a concise digest of fundamental kinds of singlemode (or low-order mode) COFs and their properties, with an emphasis on applications in two basic fields: instrumentation and telecommunications.

20

Światłowody fotoniczne

Grabiec W.

Biuletyn Wojskowej Akademii Technicznej

|

2006

|

Vol. 55, nr sp.

241-256

PL

Światłowody fotoniczne stanowią nową klasę włókien optycznych, charakteryzujących się wieloma nowymi, niezwykle interesującymi właściwościami. Jedną z nich jest możliwość kształtowania parametrów włókna poprzez modelowanie parametrów jego geometrii na etapie poprzedzającym proces produkcji. W artykule przedstawiono ideę działania światłowodów fotonicznych, ich klasyfikację, budowę oraz własności, które są przydatne głównie pod kątem aplikacji telekomunikacyjnych.

EN

Photonic crystal fibers (PCFs) are a new class of fiber optics that are characterized by a set of new interesting features. One of them is the possibility of shaping the fiber parameters through modelling its geometry before a production process. The idea of PCFs operation, their structures and features in the light of using them in telecommunication applications are presented as well. Short characteristic of manufacturing methods of PCFs are also presented here.