共查询到19条相似文献,搜索用时 187 毫秒
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实验中通过互组跃迁689 nm激光抽运形成三重态最低能态原子布居,引入688 nm激光改变三重态最低能态间的原子布居,利用抽运光与探测光空间分离的方法观测碱土金属锶原子的三重态能态间跃迁(5s6s)3S1 → (5s5p)3Pj(j=0,1,2)的吸收谱线,对应三条跃迁线的激光波段为679 nm, 688 nm和707 nm.探测三重态原子跃迁谱线可以用于锶原子冷却中再抽运光707 nm和679 nm激光频率的直接锁定,相比于通常利用的腔传递技术,可以把再抽运光频率锁定在原子跃迁谱线上,有利于提高锶原子冷却中俘获原子数目的长期稳定性. 相似文献
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表述了钠D2线跃迁所包含的24个磁子能级的原子在一维σ+-σ-冷却光和再抽运光中产生的稳态多普勒冷却力。讨论了不同磁场强度、不同再抽运光强和失谐情况下原子的多普勒冷却力及对磁光陷阱中最大捕陷速度、原子数目及温度的影响 相似文献
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光钟物理系统的小型化是制约可搬运光钟及空间冷原子光钟发展的重要因素.主要介绍了小型化锶原子光钟物理系统的研制实验.采用真空腔内置反亥姆霍兹线圈,构建一个小电流、低功耗及小体积的磁光阱.实验中测得真空线圈通电电流仅为2 A时,磁光阱中心区域轴向磁场梯度可达到43 Gs/cm,完全满足锶原子多普勒冷却与俘获对磁场梯度的要求.目前已经成功将锶原子光钟物理系统体积缩小至60 cm×20 cm×15 cm,约为实验室原锶光钟物理系统体积的1/10,并且实现了锶原子的一级冷却,测得俘获区冷原子团的直径为1.5 mm,温度约为10.6 mK.锶同位素~(88)Sr和~(87)Sr的冷原子数目分别为1.6×10~6和1.5×10~5.重抽运激光707和679 nm的加入,消除了冷原子在~3P_2和~3P_0两能态上的堆积,最终可将冷原子数目提高5倍以上. 相似文献
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表述了钠D2线跃迁包含的24个磁子能级的原子在一维σ^+~σ^-冷却光和再抽运光中产生的稳态多普勒冷却力,讨论了不同磁场强度,不同再抽动光强和失谐情况下原子的多普勒冷却力及对磁光陷阱中最大捕陷速度,原子数目及温度的影响。 相似文献
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采用原子汽室磁光阱技术实现铯原子的激光冷却与俘获 总被引:1,自引:0,他引:1
近10年来,中性原子的激光冷却与俘获方面的研究极为活跃,取得了许多重要的进展。其中,1990年Wieman等人提出的直接工作在原子汽室中的磁光阱[1],相对简化了原子冷却与俘获的装置和技术,使这方面的研究得以进一步推广和促进。由于冷原子在玻色-爱因斯... 相似文献
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在获得光致原子解吸附(light-induced atom desorption,LIAD)效应的基础上,从理论和实验方面分析了LIAD对铯原子磁光阱装载的动力学过程的影响,特别是背景原子对磁光阱的影响.通过实验获得了不同光强和照射时间下关闭解吸附光后磁光阱中铯原子的衰减过程,理论模型定量地描述了背景铯原子造成压强的变化及其对最终平衡态下真空度的影响.该研究对中性原子的长时间俘获,有效控制磁光阱中原子的装载过程具有重要意义.
关键词:
光致原子解吸附
磁光阱
激光冷却与俘获 相似文献
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研究表明,Rb原子磁光阱中所囚禁的原子数目对囚禁光的光强和失谐量,回泵光的强度以及磁场梯度有很大的依赖关系.用二能级系统模型对囚禁原子数目随囚禁光的光强和失谐量的变化关系进行了预估,理论预测的结果与实验结果定性符合.实验结果也展示了囚禁原子数目随回泵光的强度和磁场梯度的变化关系,要定量解释这些实验结果则需要更复杂的理论模型.通过囚禁原子数目对实验参数依赖关系的研究,得到特定的实验参数,来获得最大数目的冷原子.
关键词:
磁光阱
冷原子 相似文献
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We report the experimental realization of a ^88Sr magneto-optical trap (MOT) operating at the wavelength of 461 nm. The MOT is loaded via a 32 cm long spin-flip type Zeeman slower which enhances the MOT population by a factor of 22. The total laser power available in our experiment is about 300mW. We have trapped 1.6 × 10^8 ^88 Sr atoms with a 679nm and 707nm repumping laser. The two repumping lasers enhance the trap population and trap lifetime by factors of 11 and 7, respectively. The ^88 Sr cloud has a temperature of about 2.3 mK, measured by recording the time evolution of the absorption signal. 相似文献
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V. B. Tiwari S. R. Mishra H. S. Rawat S. Singh S. P. Ram S. C. Mehendale 《Pramana》2005,65(3):403-411
We present results of a study of frequency stabilization of a diode laser (λ = 780 nm) using the Doppler-free dichroic lock
(DFDL) technique and its use for laser cooling of atoms. Quantitative measurements of frequency stability were performed and
the Allan variance was found to be 6.9 × 1011 for an averaging time of 10 s. The frequency-stabilized diode laser was used to obtain the trapping beams for a magneto-optic
trap (MOT) for Rb atoms. Using the DFDL technique, the laser frequency could be locked over a wide range and this enabled
measurement of detuning dependence of the number and temperature of cold atoms using a relatively simple experimental set-up. 相似文献
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We demonstrate an experimental setup for the production of a beam source of cold 87Rb atoms. The atoms are extracted from a trapped cold atomic cloud in an unbalanced three-dimensional magneto-optical trap. Via a radiation pressure difference generated by a specially designed leak tunnel along one trapping laser beam, the atoms are pushed out continuously with low velocities and a high flux. The most-probable velocity in the beam is varied from 9 m/s to 19 m/s by varying the detuning of the trapping laser beams in the magneto-optical trap and the flux can be tuned up to 4×109 s-1 by increasing the intensity of the trapping beams. We also present a simple model for describing the dependence of the beam performance on the magneto-optical trap trapping laser intensity and the detuning. 相似文献
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B. B. Zelener S. A. Saakyan V. A. Sautenkov A. M. Akulshin E. A. Manykin B. V. Zelener V. E. Fortov 《JETP Letters》2014,98(11):670-674
A setup for laser cooling and confining of 7Li atoms in a magneto-optical trap has been built. The possibility of cooling and trapping of 7Li atoms in a wide range of frequency detuning of the cooling laser has been proved experimentally. Independent information on the density and number of ultracold 7Li atoms on various ground-state sublevels, as well as on the temperature of the atoms, has been obtained with the use of a probing tunable laser. This information is important for preparing an ultracold plasma and Rydberg matter. 相似文献
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T. Chanelière L. He R. Kaiser D. Wilkowski 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(3):507-515
The intercombination line of strontium at 689 nm is
successfully used in laser cooling to reach the photon recoil limit
with Doppler cooling in a magneto-optical traps (MOT). In this paper,
we present a systematic study of the loading efficiency of such a
MOT. Comparing the experimental results to a simple model allows us
to discuss the actual limitation of our apparatus. We also study in
detail the final MOT regime emphasizing the role of gravity on the
position, size and temperature along the vertical and horizontal
directions. At large laser detuning, one finds an unusual situation
where cooling and trapping occur in the presence of a high bias
magnetic field. 相似文献
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Realization of a single-beam mini magneto-optical trap: A candidate for compact CPT cold atom-clocks
We have demonstrated the experimental realization of a single-beam mini magneto-optical trap of 87Rb atoms, originally designed for a cold atom-clock with coherent population trapping (CPT). Only one beam is used as cooling, trapping and repumping beams rather than the three pairs of orthogonal beams of the standard magneto-optical trap. The core optics, which consists of a modified pyramidal funnel type mirror, a quarter-wave plate and a retroreflect mirror, is installed inside a mini titanium cubic chamber. The vacuum system, rubidium source, magnetic field coils and beam expander are designed in a compact geometry. As many as 1.1 × 107 rubidium atoms are cooled and trapped, and thus the mini trap is ready for the implementation of a novel compact coherent population trapping cold atom-clock. 相似文献
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E. Kirilov S. Putterman 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(3):683-691
We describe an efficient way to photoionize strontium atoms in a linear radio-frequency trap. We use a 2-photon second order
process to excite the autoionization resonance (4d2+5p2) 1D2 in neutral strontium (Sr). A doubled Ti:sapphire laser system is used at 431 nm to provide 100 fs pulses at 82 MHz. The fabrication
of the laser systems for addressing the Sr+ transitions necessary for laser cooling and excitation of quantum jumps, vacuum system and ion trap structure are also described.
With the current setup a easy and repeatable trapping of linear ion chains is readily achieved at very low Sr vapor pressures. 相似文献
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为了制备适于原子干涉仪实验的低温锂原子样品,开展了锂原子的塞曼减速及与磁光阱囚禁相关的实验研究.设计并实现了一种结构紧凑的腔体内冷式多级线圈叠加的塞曼减速器,将速度小于600 m/s的7Li原子减速到60 m/s,磁光阱装载速率为5×108/s,囚禁原子数目1×109个,原子团的最低温度约为220±30μK.研究了光学黏胶中7Li原子的寿命与囚禁光频率失谐量的关系.这些结果为进一步开展7Li原子亚多普勒冷却、光势阱蒸发冷却以及原子干涉仪实验奠定了基础. 相似文献