Optical Pulse Generation
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Sistemas CDMA ópticos coerentes baseados em codificação de fase espectral / Coherent optical CDMA systems based on spectral phase coding
In this work we perform a comprehensive analysis of a spectral phase-encoded time spreading optical code division multiple access (SPECTS-OCDMA) system. Despite being a numerical study, efforts were concentrated on the investigation of more realistic scenarios using as much information as possible from implemented test-beds in laboratories. In this context,
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/12/2012
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2. AnÃlise de performance de sÃlitons Ãpticos espaÃo-temporais em guia planar com nÃo-linearidade cÃbico quintica periodicamente modulada e circuitos lÃgicos operando nos regimes Kerr instantÃneo e relaxado. / Performance analysis of the spatio-temporal optical solitons in a planar guide with cubic quintic nonlinearity periodically modulated and logic circuits operating in regimes Kerr instantaneous and relaxed.
In this work, the propagation and stability of spatiotemporal optical solitons (or optical bullets) in a planar waveguide with periodically modulated cubic-quintic nonlinearity is presented numerically as a function of the amplitudes of modulation , the frequency of modulation and the propagation distance .With the objective of ensure the stability and preve
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/03/2010
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3. Geração de supercontínuo em fibra óptica de cristal fotônico com núcleo de água
Photonic crystal fibers (PCFs) are optical fibers whose core is surrounded by a regular matrix of holes that is responsible for light confinement and guidance. This new architecture opens new perspectives in the development of nonlinear applications, many of which are based upon the high efficiency with which nonlinearity-driven spectral broadening known sup
Publicado em: 2008
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4. Electrooptic combinator for ultra-fast pulsed microwave signal generation / Combinador eletro-optico para geração de sinais pulsados ultra-rapidos de microondas
A novel technique of pulsed microwave waveform generation has been developed. It is based on the mixture of two arbitrary signals, an ultra-fast pulse train and a microwave carrier, all generated from different sources and combined in the optical domain in order to preserve the spectral and temporal features as much as possible. The technique s concepts and
Publicado em: 2007
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5. Amplificadores Ãpticos, estudos de polarizaÃÃo e geraÃÃo de pulso usando processos paramÃtricos em fibras Ãpticas
The recent telecommunication development can be, to a large extent, attributed to the capacity of transmitting information (video, sound and data) at high transmission rates (Tbits/s) through the optical fiber. The constant advances in the technological development of active and passive devices based on optical fibers have enabled a steady increase in commun
Publicado em: 2007
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6. Nonlinear optical properties of some newly developed crystals for measurement of ultrafast laser pulses
Second harmonic generation (SHG) in nonlinear optical crystal is well-established technique for the measurement of the pulse-width of ultrafast femtosecond laser pulses. However, only selected nonlinear crystalline materials are suited for this purpose due to the limitations in transparency cut-off, limited phase-matching wavelength range, and large differen
Brazilian Journal of Physics. Publicado em: 2006-12
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7. ULTRA-SHORT OPTICAL PULSES GENERATION USING RATIONAL MODE-LOCKING IN FIBER LASERS / GERAÇÃO DE PULSOS ÓPTICOS ULTRACURTOS USANDO A TÉCNICA DE MODE-LOCKING RACIONAL EM LASERS A FIBRA
This work describes a simple and stable harmonically mode- locked erbium-doped fiber ring laser, that produces high power, ~ 1 ps transform-limited sech optical pulses. Pulse trains with different high repetition rates were obtained using harmonic mode-locking and rational harmonic mode- locking techniques. The temporal and spectral characteristics of the pu
Publicado em: 2000
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8. MEDIÇÃO DE PULSOS CURTOS EM LASER SEMICONDUTOR USANDO A GERAÇÃO INTERNA DE SEGUNDO HARMÔNICO / MEASUREMENT OF SHORT PULSES IN SEMICONDUCTOR LASER USING INTERNAL SECOND-HARMONIC GENNERATION
In this work the implementation of a measurement system of short optical pulses generated by semiconductor lasers is presented. This indirect method estimates the pulse duration using the internally generated second harmonic radiation from these lasers. The main theoretical and experimental considerations related with the second harmonic emission are also pr
Publicado em: 1993
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9. Aplicações de fibras opticas na geração de pulsos opticos ultracurtos
We have investigated picosecond nonlinear processes in optical fibers and their applications to ultrashort light pulse generation. Several experiments were performed in which we studied the role of stimulated Raman scattering, self and cross-phase modulation combined with group velocity dispersion on the generation of u1trashort pulses. In the first experime
Publicado em: 1990
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10. Generation of ultra-intense single-cycle laser pulses by using photon deceleration
A scheme to generate single-cycle laser pulses is presented based on photon deceleration in underdense plasmas. This robust and tunable process is ideally suited for lasers above critical power because it takes advantage of the relativistic self-focusing of these lasers and the nonlinear features of the plasma wake. The mechanism is demonstrated by part
The National Academy of Sciences.
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11. Optical measurement of voltage-dependent Ca2+ influx in frog heart.
Sarcolemmal Ca2+ movements in frog ventricular strips were measured by monitoring Ca2+ depletion from the extracellular space with an impermeant Ca indicator dye, antipyrylazo III. Ca2+ depletion was measured as a weighted average of light signals recorded simultaneously at three different wavelengths. This weighting procedure was designed to reduce the moti