共查询到18条相似文献,搜索用时 467 毫秒
1.
2.
为实现锶原子光钟的空间应用,采用永磁体塞曼减速器,可有效规避塔状线圈造成的高功耗和体积占比大的问题,利于光钟的空间化发展。基于永磁体构建锶光钟的环状和柱状塞曼减速器,在减速原理、磁场构建和样品研制方面各有优劣,利用多普勒测速法可对两种减速器的减速效率进行测量,可将两种减速器的减速分布曲线累计分布后对比。实验结果表明:两种永磁体塞曼减速器都达到一定减速效果,但环状永磁体塞曼减速器在体积和减速效果上,相较单x方向的柱状永磁体塞曼减速器,体积减少了60%,重量减少了80%,减速效果部分区域效率高一倍,因此优势更为显著。进一步采用环状永磁体塞曼减速器俘获锶原子的三种同位素,完成了小型化锶原子光钟的一级俘获,满足零功耗、体积小的紧凑化光钟设计需求。 相似文献
3.
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
4.
5.
6.
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
7.
8.
87Sr原子存在核自旋,在磁场作用下原子能级会分裂成不同塞曼子能级.通过光抽运对原子进行自旋极化,其自旋极化谱线的探测为锶光钟系统的闭环锁定提供精确的频率参考.本文对~(87)Sr原子钟跃迁能级5s~2~1S_0→5s5p~3P_0中的m_F=+9/2和m_F=-9/2的塞曼磁子能级自旋极化谱线进行了探测.经过一级宽带冷却和二级窄线宽冷却与俘获后,锶冷原子温度为3.9μK,原子数目为3.5×10~6.利用邻近"魔术波长"的813.426 nm半导体激光光源实现水平方向的一维光晶格装载.采用归一化探测方法用线宽为Hz量级的698 nm钟激光对~1S_0→~3P_0偶极禁戒跃迁进行探测,在150 ms的探测时间下获得线宽为6.7 Hz的钟跃迁简并谱.在磁光阱竖直方向施加一个300 mGs的偏置磁场获得塞曼分裂谱,并通过689 nm的圆偏振自旋极化光进行光抽运,最终在探测时间为150 ms时,获得左右旋极化谱线线宽分别为6.2 Hz和6.8 Hz. 相似文献
9.
10.
11.
We report the first experimental realization of magnetic trapping of a sample of cold radicals following multistage Zeeman deceleration of a pulsed supersonic beam. H atoms seeded in a supersonic expansion of Kr have been decelerated from an initial velocity of 520 m/s to 100 m/s in a 12-stage Zeeman decelerator and loaded into a magnetic quadrupole trap by rapidly switching the fields of the trap solenoids. 相似文献
12.
We build a Zeeman slower with consecutive coils and use it to load an Yb magneto-optical trap(MOTs).Cooling efficiency is measured by the fluorescence intensity of the atomic cloud trapped by the MOT.An optimized magnetic field profile can acquire the maximum cooling efficiency,corresponding to a good compromise between the smaller magnetic field mismatch and the high capture velocity.Our studies provide useful information on how the performance of the Zeeman slower can be improved. 相似文献
13.
We develop a permanent-magnet Zeeman slower with adjustable magnets along the longitudinal and radial directions.Produced by four arrays of cylindrical magnets, the longitudinal magnetic field in the slower is tunable if relevant parameters vary, for example, laser detuning or intensity. The proposed Zeeman slower can be reconfigured for Sr atoms. Additionally,we demonstrate that the residual magnetic field produced by the permanent magnets in the magneto-optical trap region can be as small as 0.5 Gs. 相似文献
14.
S. Singh V. B. Tiwari S. R. Mishra H. S. Rawat 《Journal of Experimental and Theoretical Physics》2014,119(3):406-411
A significant enhancement in the number of cold atoms in an atomic-beam-loaded magneto-optical trap (MOT) for metastable krypton atoms is observed when hollow laser beams are used in a Zeeman slower instead of a Gaussian laser beam. In the Zeeman slower setup, a combination of two hollow laser beams, i.e., a variable-diameter hollow beam generated using a pair of axicon lenses superimposed on a fixed-diameter hollow beam, has been used to reduce the longitudinal velocity of the atoms in the atomic beam below the capture speed of the MOT. The observed enhancement in the number of atoms in the MOT is attributed to reduced destruction of the atom cloud in the MOT and increased cooling of the off-axis atoms in the atomic beam, resulting from the use of hollow beams in the Zeeman slower. 相似文献
15.
R. Jung S. Gerlach R. Schumann G. von Oppen U. Eichmann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,23(3):415-419
We report on the first successful loading of a magneto-optical trap (MOT) with metastable He atoms from a Stark-slower. Thereby,
deceleration of the atoms relies on laser-atom interaction in an inhomogeneous electric field. We show that the results obtained
are comparable with early results from other groups achieved with a Zeeman slower. The Stark slower, which is able to fully
control the final velocity of the atomic He beam, is the first step in achieving complete spin independent kinematic control
based solely on electric fields.
Received 2 October 2002 / Received in final form 20 January 2003 Published online 29 April 2003
RID="a"
ID="a"e-mail: eichmann@mbi-berlin.de 相似文献
16.
We demonstrate that transitions between Zeeman-split sublevels of Rb atoms are resonantly induced by the motion of the atoms (velocity: approximately 100 m/s) in a periodic magnetostatic field (period: 1 mm) when the Zeeman splitting corresponds to the frequency of the magnetic field experienced by the moving atoms. A circularly polarized laser beam polarizes Rb atoms with a velocity selected using the Doppler effect and detects their magnetic resonance in a thin cell, to which the periodic field is applied with the arrays of parallel current-carrying wires. 相似文献
17.
S. Singh V. B. Tiwari S. R. Mishra H. S. Rawat 《Journal of Experimental and Theoretical Physics》2018,126(4):441-445
We report the studies on the effect of Zeeman slower beam power on the loading rate and collision loss rate in an atomic beam loaded krypton magneto-optical trap (MOT). The results show that an increase in Zeeman slower beam power initially increases the MOT loading rate and reduces the background collision loss rate to increase the number of cold atoms in the MOT to an optimum value. With further increase in the Zeeman slower beam power, the number of cold atoms in the MOT decreases due to increased background collision loss rate and decrease in the trap loading rate. However, the cold collision loss rate is observed to remain unaffected by the variation in the Zeeman slower beam power. Therefore, the study emphasizes the need to optimize the Zeeman slower beam power to trap maximum number of cold atoms in an atomic beam loaded MOT. 相似文献
18.
We have observed a dispersionlike absorption (or gain) spectrum at the D1 transition in a Rb vapor cell filled with a buffer gas, due to Zeeman coherence of the ground states in a double Lambda configuration. Meanwhile, we have also observed superluminal pulse propagation. It is experimentally demonstrated that the front speed of a light pulse still equals the light speed c in vacuum, although the group velocity of the light pulse is(-2.2+/-0.6) x 10(4) m/s. 相似文献