Optical Pumped
Mostrando 1-12 de 18 artigos, teses e dissertações.
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1. Ressonadores de microdiscos com região ativa nanoestruturada bombeados por injeção eletrônica / Microdisk resonators with nanostructured active region pumped by electronic injection
This doctorate¿s thesis presents the growth of InAs quantum dots directly on high bandgap InGaAsP (?g=1420 nm) barriers to be used as the active region of microdisk resonators with emission in the C-band (1520¿1570 nm). Based on photoluminescence and atomic force microscopy experiments, the occurrence of inter-diffusion on the InAs/InGaAsP interface is cal
Publicado em: 2010
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2. Desenvolvimento de um laser de Nd:YLF bombeado por diodo laser e duplicado em frequencia para 657 nm / Development of a diode pumped Nd:YLF laser, frency doubled to 657 nm
Atomic clocks are used today in a number of scientific and technological applications, ranging from tests of relativity, or variations of fundamental constants, to the use in navigation and telecommunication. The next generation of such high precision devices will be based on optical transitions of suitable laser cooled and trapped atoms. In this work we des
Publicado em: 2009
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3. Otimização da eficiência do modo TEM00 em lasers de Nd:YLF de alta potência bombeados lateralmente / TEM00 MODE EFFICIENCY ENHANCEMENT IN HIGH POWER DIODE-SIDEPUMPED Nd:YLF LASERS
For many laser applications high beam quality in fundamental mode is necessary. In this work we study the conditions that achieve high efficiency and high beam quality by optimizing the overlap between the fundamental mode and the excited region inside the active medium, using novel cavities. The highest efficiency reported so far for diode side pumped 1053
Publicado em: 2008
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4. Bombeamento optico de moleculas polares por laser selado de 13 ANTPOT. ( C O IND. 2 ) para geração de ondas Terahertz / Optically pumped of polar molecules for sealled-off 13 ANTPOT. ( C O IND. 2 ) laser for generation Terahertz waves
Neste trabalho realizamos três importantes etapas: 1) montar e caracterizar um laser selado de 13C02, 2) empregar o laser selado de 13C02 como fonte de bombeamento óptico para a molécula de metanol CH30H, e utilizá-lo pela primeira vez, para excitar o isótopo de metanol 13CH30H para geração de ondas na região do TeraHertz (THz) e 3) Propor "assignmen
Publicado em: 2007
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5. Estudo de amplificadores parametricos para sistemas de comunicações opticas de altas taxas de transmissão / Study of parametric amplifiers for high bit rate optical communication systems
This thesis presents a theoretical and experimental study on fiber optics parametric amplifiers. For the double-pumped case, we show the performance of the amplifier in terms of spectral bandwidth and gain uniformity, both fundamental properties for WDM applications. By using short dispersion shifted fibers and highly non-linear fibers, we made parametric am
Publicado em: 2006
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6. Laser de faces clivadas com regiões ativas nanoestruturadas bombeados por injeção eletronica / Cleaved face laser with nanostructured active region pumped by electronic injection
This masters dissertation presents the theoretical studies on the calculation of optical gain in nanostructures based on the InGaAs/InGaAsP/InP system. From the time dependent perturbation theory, where perturbation is the interaction of an electromagnetic wave with matter, and the Kanes theory for semiconductors band structure, relating the transition m
Publicado em: 2006
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7. Optical Amplifiers for High Capacity Multichannel Communication Systems / Amplificadores Ãpticos para Sistemas de ComunicaÃÃo Multicanais de Alta Capacidade
The ever increasing demand for data traffic suggests the capacity expansion of optical communication systems. One can obtain this by increasing the number of transmitted channels in alternative optical bands. To achieve this it is necessary to develop optical amplifers for each band. The most common amplifiers are EDFA. Nevertheless, Raman amplifiers and TDF
Publicado em: 2005
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8. Amplificadores Ãpticos a fibras dopadas com TÃlio para a banda "S"
Due to the ever increasing amount of data traffic it has become necessary to expand the capacity of optical communication systems. This can be achieved by increasing the number of transmitted channels using Wavelength Division Multiplexing. Due to improvements of the manufacturing process of optical fibers, it is possible to use the entire low-loss spectral
Publicado em: 2005
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9. CRESCIMENTO E CARACTERIZAÇÃO DE FIBRAS MONOCRISTALINAS DE FLUORETOS DO TIPO LiY1-xTRxF4 (TR = TERRAS-RARAS) / GROWTH AND CHARACTERIZATION OF FLUORIDE CRYSTALLINE FIBRES TYPE LiY1-xTRxF4 (RE = RARE-EARTH)
In this work we present the growth and characterization of LiF and pure and rare-earth doped (Er and Nd) yttrium-lithium tetra-fluoride (LiYF4 or YLF) by the micro-pulling-down technique (µ-PD). The use of this technique is original for the present purpose. A m-PD prototype in the resistive mode was firstly built to understand the most important operational
Publicado em: 2005
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10. Fabricação de multicamadas de Quantum Dots de PbTe por laser ablation
This thesis was dedicated to the fabrication of thin films, quantum dots and multilayer ofIV-VI semi conducting materiaIs by pulsed-Iaser deposition (PLD). In the first part we report on the construction of a "home made" facility for pulsed laser deposition. The basic experimental set-up fabricated for PLD consists of a vacuum chamber pumped to a base pressu
Publicado em: 2004
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11. Simplified slab waveguide three-level model for short length EDFA pumped at 1.48 mum
We adopt a three-level scheme for the pump - amplification process in 1.48 mum pumped Erbium-Doped Fiber Amplifiers, which reproduces the main experimental features of amplifiers with short and long fiber lengths. Continuous wave amplification in a simplified slab waveguide structure is simulated by means of the scalar Beam Propagation Method, taking into ac
Brazilian Journal of Physics. Publicado em: 2003-03
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12. Caracterização espectroscópica de possíveis meios ativos para lasers de Nd3+ e Tm3+ / Spectroscopic characterization of possible Nd3+ and Tm3+ laser active media
In this work we have made an important contribution to the growing research of new laser materials that can be pumped by low cost diode lasers or by the Upconversion process to operate in the near-infrared and visible spectral regions. Three kinds of hosts, doped with the rare earth ions (Nd3+ and Tm3+) were studied, and they present potential characteristic
Publicado em: 2003