Optical Amplification
Mostrando 1-12 de 53 artigos, teses e dissertações.
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1. Prospects for Developing Low-Cost Optical Fiber Sensors for Liquid-Liquid Interface Detection
Abstract This work examines the prospects of a low-cost retroreflection optical sensor system for detection of the interface between two immiscible liquids, for applications in oil separation tanks. The sensor in its simplest configuration comprises a bare fiber optic tip, cleaved at an angle of 90º relative to the longitudinal fiber axis. The device tested
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
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2. High-Speed Pulse Sequences through Semiconductor Optical Nonlinear Amplification and Buried Fiber Propagation
Abstract Microwave pulse bursts were obtained through optical domain intensity modulated microwave carriers, sliced by cascaded modulator technique, followed by non-linear semiconductor optical amplifier (SOA) pre-chirp. After 3 to 18 km of buried fiber propagation and photo detection, the microwave signals presented increased extinction ratio, up to 36 GHz,
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
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3. Interplay between Near-Field Properties and Au Nanorod Cluster Structure: Extending Hot Spots for Surface-Enhanced Raman Scattering
Materials science has observed a continuous increase in the use of metal nanoparticles in a wide range of studies, from fundamental physics to technological applications such as photocatalysis and optical communication devices. This broad scope has the same fundamental origin, the localized surface plasmons, whose excitation leads to strong light confinement
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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4. Study and Optimization of Raman Amplifiers in Tellurite-Based Optical Fibers for Wide-Band Telecommunication Systems
Abstract Here we present a numerical analysis and the optimization of a multi-pump discrete Raman amplification system based on the use of a Tellurite optical fiber as the gain media. By using previously reported optimization techniques we were able to exploit the high Raman gain of Tellurite optical fibers and its multipeak spectrum to achieve amplification
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 19/06/2019
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5. Submicroscopic malaria parasite carriage: how reproducible are polymerase chain reaction-based methods?
The polymerase chain reaction (PCR)-based methods for the diagnosis of malaria infection are expected to accurately identify submicroscopic parasite carriers. Although a significant number of PCR protocols have been described, few studies have addressed the performance of PCR amplification in cases of field samples with submicroscopic malaria infection. Here
Mem. Inst. Oswaldo Cruz. Publicado em: 2014-02
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6. Spectrally-efficient 17.6-Tb/s DWDM optical transmission system over 678 km with pre-filtering analysis
We present and analyze a 17.6-Tb/s DWDM optical transmission composed of 79 channels with 224-Gb/s RZ-DP-16QAM modulation format per-channel and coherent detection. A maximum reach of 678 km is obtained with an optical recirculation loop composed by 226 km of pure-silica core fibers and EDFA amplification only in a 50-GHz grid system with spectral efficiency
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-12
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7. Spectrally-efficient 17.6-Tb/s DWDM optical transmission system over 678 km with pre-filtering analysis
We present and analyze a 17.6-Tb/s DWDM optical transmission composed of 79 channels with 224-Gb/s RZ-DP-16QAM modulation format per-channel and coherent detection. A maximum reach of 678 km is obtained with an optical recirculation loop composed by 226 km of pure-silica core fibers and EDFA amplification only in a 50-GHz grid system with spectral efficiency
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2013-06
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8. Espectroscopia ultrarrápida do polímero semicondutor luminescente MEH-PPV com excitação no ultravioleta / Ultrafast spectroscopy of the luminescent semiconducting polymer MEH-PPV with ultraviolet excitation
The optoelectronics industry is currently undergoing a transition period in which inorganic materials are being replaced by organic materials, oligomers and polymers, in the fabrication of some types of devices. However, factors such as low efficiency and low lifetime prevent polymer based devices on entering the market definitely. The solution of these issu
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 17/08/2012
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9. Sistemas de sensores ópticos baseados em fibra óptica de perfil-W dopada com Érbio / Optical sensing systems based on Erbium-doped W-fiber
Depressed-cladding (often referred to as dual-clad or "W"- fiber) fibers with fundamental-mode cutoffs provide high distributed losses at long wavelengths and low losses at short wavelengths. The magnitude of the abrupt transition between low-loss at short wavelengths and high-loss at long wavelengths exceeds 200 dB/km and is found to be extremely sensitive
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/07/2012
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10. Estudo de esquemas de amplificação para redes PON de longo alcance / Study amplification schemes for long reach PON networks
O surgimento de novos serviços que requerem uma largura de banda cada vez maior, bem como o crescente número de usuários de tais serviços, têm introduzido desafios às empresas operadoras de telecomunicações em sua capacidade de atender a estas demandas sem perda apreciável da qualidade de serviço e mantendo, ainda assim, os custos num nível aceit�
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 12/04/2012
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11. Avaliação da indiferenciação celular e indução de neurodiferenciação em co-cultivo de fibroblastos NIH 3T3 com células mononucleares do sangue de cordão umbilical
Cellular therapy represent a new frontier for the treatment of several diseases, including diseases related to central nervous system. Human umbilical cord blood is an attractive source of stem cells; however, it has a heterogeneous population with a small amount of mesenchymal stem cells. Currently, cell reprogramming induced by different methodologies can
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/01/2012
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12. Experimental analysis of all-optical 4-ASK signal generation through parametric amplification
We present experimental results concerning a new alloptical technique that multiplexes two binary signals into a quaternary one (4-ASK). The technique is based on parametric amplification. Values of the quaternary levels obtained experimentally, as a function of the extinction ratios of the binary input signals, show a rather good agreement with the simulate
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2012-06