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Proposição e estudo de fibras ópticas microestruturadas tipo D: gerenciamento de dispersão e alta birrefringência; Proposal and study of microstructured optical fiber D-type: dispersion management and high birefringence

Spadoti, Danilo Henrique
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 02/10/2008 PT
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Este trabalho de doutoramento propôs investigar novas configurações geométricas para as fibras ópticas microestruturadas a base de sílica. Aproveitando-se da flexibilidade que sua geometria proporciona, diferentes das fibras ópticas convencionais, foram propostas fibras ópticas microestruturadas com perfil tipo D atuando, especificamente, em duas aplicações distintas: fibras compensadoras de dispersão ou fibras altamente birrefringentes. Para o estudo teórico das fibras ópticas microestruturadas foram utilizados dois métodos numéricos: o método da Sobre-Relaxação Sucessiva (SOR) e o método de Arnoldi Implicitamente Reiniciado (IRAM). Foi necessário implementar o método IRAM para determinar os modos de mais alta ordem presentes em guias de onda multimodos, uma vez que o método SOR fornece apenas a solução para o modo fundamental. Neste contexto, as fibras ópticas microestruturadas com perfil D, propostas e investigadas neste trabalho, demonstraram ser extremamente promissoras para atuar na compensação da dispersão cromática ou no aumento do efeito da birrefringência. Foram projetadas fibras capazes de compensar a dispersão em banda larga, cobrindo as bandas de telecomunicações S, C e L, ou, ainda, fibras com um alto coeficiente de dispersão negativo em torno do comprimento de onda de 1550nm. Adicionalmente...

Experimental observation of infrared spectral enlargement in As 2S3 suspended core microstructured fiber

El-Amraoui, M.; Fatome, J.; Jules, J. C.; Kibler, B.; Gadret, G.; Skripatchev, I.; Messaddeq, Y.; Renversez, G.; Szpulak, M.; Troles, J.; Brilland, L.; Smektala, F.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência
ENG
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The development of chalcogenide glasses fibers for application in the infrared wavelength region between 1 and 10 μm is a big opportunity. More particularly, the possibility to generate efficient non linear effects above 2 μm is a real challenge. We present in this work the elaboration and optical characterizations of suspended core microstructured optical fibers elaborated from the As2S3 chalcogenide glass. As an alternative to the stack and draw process a mechanical machining has been used to the elaboration of the preforms. The drawing of these preforms into fibers allows reaching a suspended core geometry, in which a 2.5 μm diameter core is linked to the fiber clad region by three supporting struts. The zero dispersion wavelength is thus shifted towards 2 μm. At 1.55 μm our fibers exhibit a dispersion around -250 ps/nm/km. Their background level of losses is below 0,5 dB/m. By pumping them at 1.55 μm with a ps source, we observe self phase modulation as well as Raman generation. Finally a strong spectral enlargement is obtained with an average output power of - 5 dbm. © 2010 SPIE.

Spectral-Domain Measurements of Birefringence and Sensing Characteristics of a Side-Hole Microstructured Fiber

Hlubina, Petr; Martynkien, Tadeusz; Olszewski, Jacek; Mergo, Pawel; Makara, Mariusz; Poturaj, Krzysztof; Urbańczyk, Waclaw
Fonte: MDPI Publicador: MDPI
Tipo: Artigo de Revista Científica
Publicado em 28/08/2013 EN
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We experimentally characterized a birefringent side-hole microstructured fiber in the visible wavelength region. The spectral dependence of the group and phase modal birefringence was measured using the methods of spectral interferometry. The phase modal birefringence of the investigated fiber increases with wavelength, but its positive sign is opposite to the sign of the group modal birefringence. We also measured the sensing characteristics of the fiber using a method of tandem spectral interferometry. Spectral interferograms corresponding to different values of a physical parameter were processed to retrieve the spectral phase functions and to determine the spectral dependence of polarimetric sensitivity to strain, temperature and hydrostatic pressure. A negative sign of the polarimetric sensitivity was deduced from the simulation results utilizing the known modal birefringence dispersion of the fiber. Our experimental results show that the investigated fiber has a very high polarimetric sensitivity to hydrostatic pressure, reaching −200 rad × MPa−1× m−1 at 750 nm.

Solid microstructured optical fiber

Feng, X.; Monro, T.; Petropoulos, P.; Finazzi, V.; Hewak, D.
Fonte: Optical Soc Amer Publicador: Optical Soc Amer
Tipo: Artigo de Revista Científica
Publicado em //2003 EN
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An all-solid microstructured fiber based on two thermallymatched silicate glasses with a high index contrast has been fabricated for the first time. The microstructured cladding was shown to be essentially unchanged during fiber drawing. Fiber attenuation was measured as 5dB/m at 1.55m by the cutback method. High nonlinearity 230 W-1km-1 has been predicted and experimentally demonstrated in this fiber at 1.55m. In addition, modeling predicts that near-zero dispersion can be achieved between 1.5-1.6m in this class of high nonlinear fiber.; Xian Feng, Tanya Monro, Periklis Petropoulos, Vittoria Finazzi and Dan Hewak

Advances in microstructured fiber technology

Richardson, D.; Poletti, F.; Leong, J.; Feng, X.; Ebendorff-Heidepriem, H.; Finazzi, V.; Frampton, K.; Asimakis, S.; Moore, R.; Baggett, J.; Hayes, J.; Petrovich, M.; Tse, M.; Amezcua, R.; Price, J.; Broderick, N.; Petropoulos, P.; Monro, T.
Fonte: IEEE; Online Publicador: IEEE; Online
Tipo: Conference paper
Publicado em //2005 EN
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We review our recent progress in the area of microstructured fiber design, fabrication and applications with particular emphasis on the control of both the nonlinearity and dispersion.; http://www.orc.soton.ac.uk/viewpublication.html?pid=3160

Exposed-core microstructured optical fibers for real-time fluorescence sensing

Warren-Smith, S.; Ebendorff-Heidepriem, H.; Foo, H.; Moore, R.; Davis, C.; Monro, T.
Fonte: Optical Soc Amer Publicador: Optical Soc Amer
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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New methods for fabricating glass exposed-core microstructured optical fiber are demonstrated. The fiber designs consist of an optical fiber with a suspended micron-scale core that is partially exposed to the external environment, which is particularly useful for sensing. These fibers allow for strong evanescent field interactions with the surrounding media due to the small core size, while also providing the potential for real-time and distributed measurements. The experimental performance of an exposed-core fiber is compared to an equivalent microstructured fiber with an enclosed (protected) core in terms of their performance as evanescent field sensors. We demonstrate that the exposed-core fiber can provide a significantly improved measurement response time.; Stephen C. Warren-Smith, Heike Ebendorff-Heidepriem, Tze Cheung Foo, Roger Moore, Claire Davis, and Tanya M. Monro

A low-volume microstructured optical fiber hydrogen peroxide sensor

Schartner, E.; Murphy, D.; Ebendorff-Heidepriem, H.; Monro, T.
Fonte: SPIE - International Society for Optical Engineering; United States Publicador: SPIE - International Society for Optical Engineering; United States
Tipo: Conference paper
Publicado em //2011 EN
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Optical fibers are ideal for environmental sensing applications because of their ability to transmit optical signals to and from the sensing region without the use of free-space optics. Through the use of suspended core MOFs we can exploit the interaction between the evanescent field of the fiber and a target molecule to facilitate detection. The aim of this work is to increase the sensitivity of the system, and to examine the primary factors such as the background glass fluorescence currently restricting the detection limit. This work is focused on biological detection in liquid samples using Quantum dots.; E. P. Schartner, D. F. Murphy, H. Ebendorff-Heidepriem, T. M. Monro

Fusion splicing soft-glass suspended core fibers to solid silica fibers for optical fiber sensing

Englich, F.; Schartner, E.; Murphy, D.; Ebendorff-Heidepriem, H.; Monro, T.
Fonte: AIP; CD Publicador: AIP; CD
Tipo: Conference paper
Publicado em //2010 EN
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We report fusion splicing of soft-glass suspended small-core fibers to conventional silica single-mode fibers for integration with conventional fiber systems. Heat-induced damage to the microstructured fiber region is minimized by using a low-power iridium filament.; Florian V. Englich, Erik P. Schartner, Dominic F. Murphy, Heike Ebendorff-Heidepriem, and Tanya M. Monro

Driving down the detection limit in microstructured fiber-based chemical dip sensors

Schartner, E.; Ebendorff-Heidepriem, H.; Warren-Smith, S.; White, R.; Monro, T.
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em //2011 EN
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We present improvements to fluorescence sensing in soft-glass microstructured optical fibers that result in significantly improved sensitivity relative to previously published results. Concentrations of CdSe quantum dots down to 10 pM levels have been demonstrated. We show that the primary limitation to the sensitivity of these systems is the intrinsic fluorescence of the glass itself.; Erik P. Schartner, Heike Ebendorff-Heidepriem, Stephen C. Warren-Smith, Richard T. White and Tanya M. Monro

Extruded microstructured fiber lasers

Oermann, M.; Ebendorff-Heidepriem, H.; Ottaway, D.; Lancaster, D.; Veitch, P.; Monro, T.
Fonte: IEEE-Inst Electrical Electronics Engineers Inc Publicador: IEEE-Inst Electrical Electronics Engineers Inc
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
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We present the first fiber laser fabricated from an extruded microstructured preform. This laser is also, to the best of our knowledge, the first microstructured tellurite glass fiber laser. The threshold and efficiency of the 980 nm pumped, 1.5 μm erbium-doped tellurite laser were measured to be 1.5 mW and 13 % respectively.; Michael R. Oermann, Heike Ebendorff-Heidepriem, David J. Ottaway, David G. Lancaster, Peter J. Veitch, and Tanya M. Monro

A microstructured optical fiber sensor for ion-sensing based on the photoinduced electron transfer effect

Richardson, A.; Foo, T.; Englich, F.; Ebendorff-Heidepriem, H.; Sumby, C.; Monro, T.
Fonte: SPIE Publicador: SPIE
Tipo: Conference paper
Publicado em //2012 EN
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We employ the photoinduced electron transfer (PET) effect within suspended-core microstructured optical fiber to authenticate a new type of fluorescence based sensor for ion detection. A sensor design based on a simple model PET-fluoroionophore system and small core microstructured optical fiber is shown and the operational performance of the sensor to different concentrations of sodium is investigated. Future approaches to improving the sensor’s signal stability and sensitivity are discussed.; Andrew C. Richardson, Tze Cheung Foo, Florian V. Englich, Heike Ebendorff-Heidepriem, Christopher J. Sumby and Tanya M. Monro

DNA detection using molecular beacon in soft-glass microstructured optical fibers

Nguyen, L.; Warren-Smith, S.; Cooper, A.; Monro, T.
Fonte: SPIE-INT SOC OPTICAL ENGINEERING Publicador: SPIE-INT SOC OPTICAL ENGINEERING
Tipo: Conference item
Publicado em //2012 EN
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We report, for the first time to our knowledge, the detection of specific strands of DNA based on a soft-glass microstructured optical fiber (MOF) platform loaded with molecular beacons (MBs). This detection scheme brings together the intrinsic advantage of MOF for low-volume sensing with a label-free approach, and is highly specific in identifying complementary (cDNA) from non-complementary (nDNA) sequences at room temperature. The detection limit of the current sensing scheme is demonstrated to be improvable via coupling to different sets of guided core modes by means of longitudinal offset in coupling light from the source to the fiber.; http://www.ofs-22.org/site/; Linh Viet Nguyen, Stephen C. Warren-Smith, Alan Cooper, Tanya M. Monro; Poster presentation

Interferometric fiber sensor using exposed core microstructured optical fiber for refractive index based biochemical sensing

Nguyen, L.V.; Warren-Smith, S.C.; Cooper, A.; Monro, T.M.
Fonte: SPIE Publicador: SPIE
Tipo: Conference paper
Publicado em //2014 EN
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We proposed and experimentally demonstrated an in-fiber interferometric-type sensor by splicing an exposed core microstructured optical fiber (ECF) with lead-in and lead-out single mode fibers (SMFs) for refractive index-based biochemical sensing applications. Due to the multimode characteristic of the ECF, several modes can be excited at the lead-in splicing point and, after propagating through the ECF section, arrive at the lead-out splicing point with different phases forming a multi-arm interference pattern in the transmission spectrum of the device. Two dominant modes were found be consistently excited by maximizing the butt coupling between ECF and SMFs. The interference fringes shifts differently upon applying liquids of different refractive index on the exposed side of the EC.; Linh Viet Nguyen, Stephen C. Warren-Smith, Alan Cooper, Tanya M. Monro

Fibras ópticas microestruturadas: modelagem e aplicações; Microstructured optical fibers: modeling and applications

Francisco, Carlos Alberto de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/08/2004 PT
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Este trabalho tem por objetivo a modelagem numérica das fibras microestruturadas e a proposição de dispositivos inovadores com base nos modelos numéricos construídos. Primeiramente, são implementados dois formalismos distintos: o FDTD (do inglês Finite Diference Time Domain) para a geração dos diagramas de bandas dos cristais fotônicos e o SOR (do inglês Successive Over Relaxation) para a análise modal das fibras. A partir destes modelos, são propostas três aplicações distintas que utilizam as propriedades inovadoras das fibras microestruturadas, a saber: compensador de dispersão a fibra com capacidade de compensar um enlace óptico com cerca de vinte vezes seu comprimento, amplificador Raman com alto ganho óptico e isolador óptico a fibra microestruturada.; The goal of this work is the numerical modeling of microstructured optical fibers and the proposition of novel applications using the model developed. First, two distinct formalisms are implemented, the Finite Difference Time Domain Method (FDTD) to generate the photonic crystal band diagrams and the Successive Over Relaxation method (SOR) to carry out modal analysis on the microstructured optical fibers. By means of these models, three applications are investigated: high performance dispersion compensation fiber...

Generation of mid-IR continuum using tellurite microstructured fiber

Delmonte, T.; Watson, M.; O'Driscoll, E.; Feng, X.; Monro, T.; Finazzi, V.; Petropoulos, P.; Price, J.; Baggett, J.; Loh, W.; Richardson, D.; Hand, D.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Conference paper
Publicado em //2006 EN
Relevância na Pesquisa
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We demonstrate the production of a well depleted mid-IR continuum with a spectral range between ~0.9 – 2.5 μm using a tellurite wagon wheel microstructured fiber and a pump source at 1.5 μm.; http://www.orc.soton.ac.uk/viewpublication.html?pid=3436

Técnica para controlar o comprimento de onda da dispersão zero de uma fibra microestruturada; Technique to control the zero¿dispersion wavelength of a microstructured optical fiber

Roddy Elky Ramos Gonzáles
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/02/2013 PT
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Propor uma técnica eficiente para controlar o Comprimento de Onda da Dispersão Zero (ZDW - Zero Dispersion Wavelength) de uma Fibra Óptica Microestruturada (MOF - Microstructured Optical Fiber). Esta técnica baseia-se na variação do índice de refração linear e na variação da espessura de um filme fino que cobre as superfícies interiores dos buracos da MOF. Foi utilizado um código potente e preciso baseado na formulação do Método dos Elementos Finitos (FEM - Finite Element Method) totalmente vetorial em conjunto com Camadas Perfeitamente Casadas (PMLs - Perfectly Matched Layers). E demonstrado um deslocamento Maximo do ZDW de 570 nm. Este filme fino pode ser incluído durante ou apos a fabricação da MOF, isso significa que a Dispersão Zero (ZD - Zero Dispersion) da fibra pode ser adaptada conforme a necessidade.; An efficient technique to control the zero-dispersion wavelength (ZDW) of a microstructured optical fiber (MOF) is proposed and numerically demonstrated in this work. This technique is based on the variation of the linear refractive index and the thickness of a thin film covering the microstructured optical fiber holes' inner surfaces. A powerful and accurate code based on a full-vector finite-element method formulation in conjunction with perfectly matched layers was used. A maximum of 570-nm zero-dispersion wavelength displacement is demonstrated. This thin film can be included after the microstructured optical fiber has been fabricated...

Efficiency of dispersive wave generation in dual concentric core microstructured fiber

Modotto, Daniele; Andreana, Marco; Krupa, Katarzyna; Manili, Gabriele; Minoni, Umberto; Tonello, Alessandro; Couderc, Vincent; Barthélémy, Alain; Labruyère, Alexis; Shalaby, Badr Mohammed; Leproux, Philippe; Wabnitz, Stefan; Aceves, Alejandro B.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 26/06/2015
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We describe the generation of powerful dispersive waves that are observed when pumping a dual concentric core microstructured fiber by means of a sub-nanosecond laser emitting at the wavelength of~1064 nm. The presence of three zeros in the dispersion curve, their spectral separation from the pump wavelength, and the complex dynamics of solitons originated by the pump pulse break-up, all contribute to boost the amplitude of the dispersive wave on the long-wavelength side of the pump. The measured conversion efficiency towards the dispersive wave at 1548 nm is as high as 50%. Our experimental analysis of the output spectra is completed by the acquisition of the time delays of the different spectral components. Numerical simulations and an analytical perturbative analysis identify the central wavelength of the red-shifted pump solitons and the dispersion profile of the fiber as the key parameters for determining the efficiency of the dispersive wave generation process.; Comment: 11 pages, 12 figures

A microstructured fiber source of photon pairs at widely separated wavelengths

Slater, Joshua A.; Corbeil, Jean-Simon; Virally, Stephane; Bussieres, Felix; Kudlinski, Alexandre; Bouwmans, Geraud; Lacroix, Suzanne; Godbout, Nicolas; Tittel, Wolfgang
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We demonstrate a source of photon pairs with widely separated wavelengths, 810 nm and 1548 nm, generated through spontaneous four-wave mixing in a microstructured fiber. The second-order auto-correlation function g^{(2)}(0) was measured to confirm the non-classical nature of a heralded single photon source constructed from the fiber. The microstructured fiber presented herein has the interesting property of generating photon pairs with wavelengths suitable for a quantum repeater able to link free-space channels with fiber channels, as well as for a high quality telecommunication wavelength heralded single photon source. It also has the advantage of straightforward coupling into optical fiber. These reasons make this photon pair source particularly interesting for long distance quantum communication.; Comment: 3 pages, 3 figures. Published version

Evolution of light trapped by a soliton in a microstructured fiber

Hill, S.; Kuklewicz, C. E.; Leonhardt, U.; Koenig, F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/05/2009
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We observe the dynamics of pulse trapping in a microstructured fiber. Few-cycle pulses create a system of two pulses: a Raman shifting soliton traps a pulse in the normal dispersion regime. When the soliton approaches a wavelength of zero group velocity dispersion the Raman shifting abruptly terminates and the trapped pulse is released. In particular, the trap is less than 4ps long and contains a 1ps pulse. After being released, this pulse asymmetrically expands to more than 10ps. Additionally, there is no disturbance of the trapping dynamics at high input pulse energies as the supercontinuum develops further.; Comment: 14 pages, 11 figures

Numerical Investigations of Interstitial Hole-assistant Microstructured Optical Fiber

Yu, Xia; Shum, Ping; Tang, M.; Yan, M.; Love, John
Fonte: National Institute of Optoelectronics Publicador: National Institute of Optoelectronics
Tipo: Artigo de Revista Científica
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We evaluate numerically the optical characteristics of a new type of microstructured optical fiber with interstitial air holes (IH-MOF). By modification of the basic hexagonal unit cell, different optical waveguide properties can be achieved. Endlessly single mode operation is obtainable from these IH-MOF structures with smaller air-hole diameter to pitch ratio (d/∧<0.25) compared with conventional triangular-latticed MOFs. The zero-dispersion-wavelength is blue-shifted with the increase of interstitial air-hole size. Leaky loss and effective mode area is significantly reduced thus the nonlinearity is enhanced by a tighter confinement.