Laser Trapping
Mostrando 1-12 de 33 artigos, teses e dissertações.
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1. Ablação tumoral fototérmica in vivo utilizando nanobarras de ouro / Photothermal tumor ablation in vivo using gold nanorods
Ultimamente têm-se buscado tratamentos menos invasivos para o câncer, como os que utilizam campos magnéticos ou luz, e dentre esses últimos, aqueles que fazem uso de materiais, geralmente metálicos, com propriedade de ressonância plasmônica de superfície. O tratamento hipertérmico encaixa-se neste perfil e já apresenta resultados promissores com na
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/02/2012
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2. Montagem e caracterização de uma armadilha magneto-óptica de rubídio / Mounting and characterization of a rubidium magneto-optical trap
In this work we present the building and characterization of a Magneto-Optical Trap (from now on named MOT) for Rubidium atoms. We perform experiments for studying the eect of a broadband light over trapped atoms. In order to carry out this study we used a incandescent lamp which is broad in the wavelength spectrum. We observed in a MOT, with a number of 109
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/07/2011
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3. Construção de uma armadilha magneto-ótica para aplicações em informação quântica e física atômica / Construction of a Magnet-Optical Trap for Aplications at Quantum Information and Atomic Physics
We built a magneto-optical trap (MOT) for rubidium as a first step for the trapping of a cloud of cold atoms in a periodic potential formed by light beams. This system will be used for experiments in atom physics, with possible applications in quantum information. A MOT is necessary to avoid the problems imposed by the thermal agitation of the atoms to the m
Publicado em: 2009
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4. Localized beams in optical tweezers with conventional and metamaterial particles / Feixes localizados em pinças opticas com particulas convencionasi e metamateriais
In this thesis, we explore some applications of localized beams in FSO - Free Space Optics - and optical tweezers, greater emphasis been given to the second one. For FSO, we show that it is possible to choose the desired longitudinal intensity pattern by using optical elements adequately modeled in their phase functions: the axicons. In this way, these beams
Publicado em: 2009
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5. Construção de uma armadilha de dipolo com laser de CO2. / Constrution of a dipole trap using a CO2 laser
In this work we present the construction of an optical dipole trap using a CO2 laser, which involves the use of news and modern technologies never utilized by our group up to now. We have builded a new trap chamber with large optical access, used atomic dispensers as an atomic source and a high power CO2 laser and its optical components. We have demonstrated
Publicado em: 2006
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6. Força optica em pinças opticas : estudo teorico e experimental / Optical force in optical tweezers : theory and experiment
The optical tweezers is an instrument capable of manipulating and trapping dielectric particles through the radiation pressure. Their applications in the life sciences and biophysics increased exponentially after it has been demonstrated that it allowed to microorganisms to be maintained alive trapped for long times. Information obtained from these experimen
Publicado em: 2006
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7. Desenvolvimento de fontes de radiação coerente na região azul com lasers semicondutores para experimentos de resfriamento e aprisionamento de atomos de calcio / Development sources of coherent radiation in the blue region with semiconductors laser for experiments of coolong and trapping of neutral calcium atoms
Esta tese apresenta o desenvolvimento de fontes de radiação coerente na região do azul baseadas em lasers semicondutores para excitar a transição de resfriamento e aprisionamento 1 S0-1P1 do Cálcio, em 423nm. Foi construído um laser de diodo em cavidade estendida emitindo em g =846 nm que foi empregado em uma configuração de Cavidade Estendida de Li
Publicado em: 2004
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8. Calcium magneto-optical trap loaded from a decelerated atomic beam
We describe a new system for laser cooling and trapping of neutral Calcium atoms employing the ¹S0 -¹ P1 resonant transition at 423 nm. An on-axis magneto-optical trap (MOT) is loaded from a Zeeman decelerated atomic beam. When a single laser is used, in order to avoid perturbation of the trap by the deceleration laser beam, this one has been tightly focus
Brazilian Journal of Physics. Publicado em: 2003-06
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9. Desenvolvimento de fontes laser, espectroscopia de alta resolução e resfriamento e aprisionamento magneto-optico de atomos de calcio
In this work, we report on an experimental system for laser cooling and magneto-optical trapping of calcium atoms, the development of the laser sources for this system, and a spectroscopic analysis of calcium transitions in hollow cathode electric discharges. In the case of calcium, the most efficient optical transition for the atom motion manipulation by ra
Publicado em: 2002
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10. Low Energy (Anti)atoms for Precision Tests of Basic Physics
Recent advances in techniques to manipulate and study, with high precision, atomic hydrogen, from one hand, and successful trapping schemes for positrons and antiprotons, from the other hand, have encouraged the pursuit of experiments to test CPT violation and the Weak Equivalence Principle (WEP) through the comparison of hydrogen and antihydrogen. A descrip
Brazilian Journal of Physics. Publicado em: 2001-06
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11. Perdas colisionais devido ao processo de mudança de estrutura fina em uma armadilha magneto-óptica de rubídio / Fine structure changing collisional losses in a rubidium magneto-optical trap
We report the observation of trap-loss collisional rates due to fine structure changing collisions between cold and trapped 85Rb atoms. We have measured, by photoionization of the atomic fragments in 5P1/2 state originated in these collisions, the rates through the atoms leave the trap induced by this loss mechanism. We carried out experiments to determine t
Publicado em: 1999
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12. Studies on Optical Shielding of Cold Collisions / Estudo de Blindagem Óptica em Colisões Frias
In this work, we showed that is possible to suppress most of the inelastic processes that may cause losses of atoms in a magneto-optical trap. Our results reveal that the process of optical shielding (demonstrated by our group, for the first time to photoassociative ionization - Phys. Rev. Lett. 73, 1911 (1994)) is much more general than it was supposed. Eve
Publicado em: 1998