Cooling Of Atoms
Mostrando 1-12 de 16 artigos, teses e dissertações.
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1. Efeito da Taxa de Resfriamento na Liga Ni80Cu20 via Dinâmica Molecular
RESUMO A simulação em Dinâmica Molecular (MD) é uma poderosa ferramenta para estudo de ligas amorfas nanométricas. Neste artigo, a MD foi empregada para o estudo da liga Ni80Cu20. As simulações foram realizadas com o código livre LAMMPS, em um sistema contendo 2.000 átomos com interação atômica dada pelo potencial de Finnis-Sinclair (EAM-FS). O a
Matéria (Rio J.). Publicado em: 20/05/2019
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2. Laser cooling techniques: standard and alternated optical molasses
The technique of laser cooling, whose basic idea was proposed in 1975 [1], provided the development of many important areas like high-resolution spectroscopy [2], atomic clocks [3] and quantum gases confined in magnetic or optical traps [4, 5]. Among the techniques applied to cooling neutral atoms is the optical molasses [6] that will be explored in this wor
Rev. Bras. Ensino Fís.. Publicado em: 22/05/2017
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3. Peltier efect in quasiperiodic structures semiconductors / Efeito Peltier em estruturas semicondutoras quasiperiódicas
There is nowadays a growing demand for located cooling and stabilization in optical and electronic devices, haul of portable systems of cooling that they allow a larger independence in several activities. The modules of thermoelectrical cooling are bombs of heat that use efect Peltier, that consists of the production of a temperature gradient when an electri
Publicado em: 2008
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4. 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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5. Obtenção da degenerescência quântica em sódio aprisionado / Achievement of quantum degeneracy in trapped sodium
Usando a técnica de resfriamento evaporativo para átomos comprimidos numa armadilha magnética tipo QUIC, implementamos experimentos para observar Condensação de Bose-Einstein de átomos de sódio. Nessa armadilha magnética temos átomos advindos de uma armadilha magneto-óptica, a qual é carregada por um feixe desacelerado como etapa de pré-resfriame
Publicado em: 2004
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6. 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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7. Experimental development to produce and study quantum gases: Bose-Einstein condensation / Desenvolvimento experimental para produção e estudo de gases quânticos: condensação de Bose-Einstein
We present here all the experimental development obtained in São Carlos to produce and study quantum degenerate gases, aiming specially the realization of Bose-Einstein Condensation (BEC) in sodium (Na-23) atoms. In order to do that we designed, built and completely integrated a complex experimental setup which conjugates most of the techniques developed al
Publicado em: 2002
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8. 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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9. 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
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10. A caracterização de laser de diodo para espectroscopia de alta resolução
In the last decade the diode lasers became the most important in economics. The use of diode lasers in Physics and Technology has expanded rapidly. This has occurred because their low cost, reliability , durability and possibility of integrating with electronic components to form integrated optoeletronic circuits. The development of novel techniques to contr
Publicado em: 1997
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11. Preparation of diode laser and its use in trapping and study of cold atoms. / Preparação de laser de diodo e sua utilização em aprisionamento e estudo de átomos frios
Este trabalho relata o desenvolvimento de todo o aparato experimental para a realização de aprisionamento de césio através de uma armadilha magneto-óptica. As fontes de luz neste processo foram os lasers de diodo e todo seu sistema para operação, estabilização e redução da largura de linha foi construído. As medidas das constantes de mola e amort
Publicado em: 1996
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12. Construção de um sistema experimental para desaceleração de átomos. / Construction of an experimental system for stopping atoms.
This work presents the development and test of an experimental set-up which allows to produce a very strong slow motion atomic beam. We discuss the calculation and construction of the solenoid to compensate the Doppler effect arising during the deceleration process, vacuum chambers, the oven which produces the atomic beam and the optical system used. We have
Publicado em: 1991