Semiconductor Laser
Mostrando 13-24 de 43 artigos, teses e dissertações.
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13. Laser effects in semiconductor heterostructures within an extended dressed-atom approach
We extend the dressed-atom approach to treat the interaction of a laser field with a semiconductor system. The semiconductor is modeled via a simple Kane band-structure scheme and the interaction with the laser field is incorporate through the renormalization of the semiconductor energy gap and conduction/valence effective masses. Far from resonances, such o
Brazilian Journal of Physics. Publicado em: 2002-06
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14. Many particle theory for the luminescence, characterization and simulation of quantum well laser structures
A photon Green's function theory is used to incorporate Bethe- Salpeter-like many body corrections in the the computations of nonlinear optical spectra of semiconductor quantum well laser materials. The numerical results presented reproduce several features found in the experimental characterization of the actual devices.
Brazilian Journal of Physics. Publicado em: 2002-06
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15. Confinamento lateral de portadores e fotons e o comportamento espectral de laser em tres terminais
The availability of semiconductor quantum-well structures increased the interest in the development of systems for optical computing and optical interconnection using semiconductor lasers as the basic component in optoelectronic integrated circuits. Therefore, there is a great interest in searching for novel materials and structures as well as fabrication te
Publicado em: 2001
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16. Mistura e geração experimental de sinais de microonda empregando amplificadores opticos semicondutores
Recently, the development of techniques that allow optical transmission and generation of microwave and millimetre-wave signals have received significant attention, mainly due to the fact that considerably low-noise optical wavelenght-division multiplexed systems are available to transmit large amounts of data throughout many points interconnected by optical
Publicado em: 1998
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17. CARACTERÍSTICAS DE MODULAÇÃO E RUÍDO EM LASERS SEMICONDUTORES MONOMODO / MODULATION CHARACTERISTICS AND NOISE IN SINGLE MODE SEMICONDUCTOR LASERS
Propriedades dinâmicas dos lasers semicondutores monomodo têm sido investigadas utilizando-se diferentes sistemas ópticos de medição. Sistemas ópticos integrados auto- homódino e heteródino foram montados para a medição da modulação em intensidade (IM) e freqüência (FM) e para a obtenção do fator de alargamento da largura de linha (alfa) de t
Publicado em: 1998
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18. Lasers semicondutores em cavidade estendida aplicados a espectroscopia de alta resolução
We use an Extended Cavity Semiconductor Laser (ECSL) to overcome some drawbacks of solitary diode lasers as limited tuning range, large linewidth and inaccessible spectral regions. The Litman-Metcalf configuration was used because of its several advantages, e.g., a very small passband due to using a grating in double passage grazing incidence. This laser con
Publicado em: 1997
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19. Crescimento seletivo de diamante assistido a laser : um estudo preliminar
The use of diamond films for semiconductor devices promises a technological advance in Electronic Industry. It?s unique combination of properties which overcome that of those semiconductors used nowadays allows a better integration and seed operation in circuits of this particular material. The subject of our Theses is about the growth of a single-crystal di
Publicado em: 1997
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20. SIMULAÇÃO E ANÁLISE DE DESEMPENHO DE SISTEMAS ÓPTICOS DIGITAIS UTILIZANDO AMPLIFICADORES ÓPTICOS A FIBRA DOPADA COM ÉRBIO / SIMULATION AND PERFORMANCE ANALYSIS OF DIGITAL SYSTEMS USING ERBIUM-DOPED FIBER AMPLIFIERS
Os amplificadores a fibra dopada com érbio (EDFAs) têm se mostrado como uma alternativa bastante atraente para aumentar a capacidade de sistemas de comunicações por fibras ópticas operando na terceira janela de transmissão de fibras convencionais (lambda = 1.55 mi m). Consideráveis esforços têm sido direcionados ao aprimoramento do desempenho desses
Publicado em: 1996
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21. STUDY OF THE INTERACTION OF A PULSED SEMICONDUCTOR LASER WITH ON EXTERNAL OPTICAL SIGNAL AND APPLICATIONS TO THE OPTICAL SAMPLING TECHNIQUE / ESTUDO DA INTERAÇÃO DE UM LASER SEMICONDUTOR PULSADO COM SINAL ÓPTICO EXTERNO E APLICAÇÕES À TÉCNICA DE AMOSTRAGEM ÓPTICA
A interação entre dois lasers semicondutores operando em regime de chaveamento de ganho foi estudada, em função do comprimento de onda e das condições de operação de cada um. Mostrou-se que um laser netas condições pode operar como um detetor com resolução de até alguns picossegundos, num sistema de amostragem óptica.
Publicado em: 1994
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22. PC-LASER : um software para simulação de lasers semicondutores
Today, the technology of PC-computer offers low cost and high performance machine that is possible to use it to simulate components and communication systems. The purpose of this work is to present the development of a specific computer enviroment to simulate and to analyse semiconductor laser diodes for applications in optical fiber telecommunication system
Publicado em: 1994
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23. Steady-state photocarrier grating techique / Técnica de grade de fotoportadores em estado estacionário
In this work we present a new and simple technique to measure transport and kinetic properties in photoconductive insulator semiconductors. Important properties as diffusion length and mobility-lifetime product of hydrogenated amorphous silicon (a-SI:h) was determined. This technique is based on the effect of a steady-state photocarrier grating concentration
Publicado em: 1994
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24. REFLECTOMETRIA COERENTE APLICADA AO ESTUDO DA INSTABILIDADE DE FREQÜÊNCIA E EFEITOS TÉRMICOS EM LASERS DE REALIMENTAÇÃO DISTRIBUÍDA / STUDY OF FREQUENCY INSTABILITY AND THERMAL EFFECTS IN DISTRIBUTAL FEEDBACK LASERS WITH COHERENT REFLECTOMETRY
Coherente reflectometry has been an important technique for characterization of optinal and optoeletronics devices used in communications systems. In this work, Coherente frequency domain reflectometry was used in the study of the Distributed-Feedback Semiconductor lasers characteristics. The measurement of thermal response of the laser module, linearity of
Publicado em: 1994