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1.
A cold atom source is important for quantum metrology and precision measurement. To reduce the quantum projection noise limit in optical lattice clock, one can increase the number of cold atoms and reduce the dead time by enhancing the loading rate. In this work, we realize an enhanced cold mercury atom source based on a two-dimensional (2D) magneto-optical trap (MOT). The vacuum system is composed of two titanium chambers connected with a differential pumping tube. Two stable cooling laser systems are adopted for the 2D-MOT and the three-dimensional (3D)-MOT, respectively. Using an optimized 2D-MOT and push beam, about 1.3×106 atoms, which are almost an order of magnitude higher than using a pure 3D-MOT, are loaded into the 3D-MOT for 202Hg atoms. This enhanced cold mercury atom source is helpful in increasing the frequency stability of a neutral mercury lattice clock. 相似文献
2.
量子投影噪声是影响光晶格钟的一个重要参数,提高磁光阱中装载率有利于降低量子投影噪声,可提升光晶格钟的性能.针对实验所用的汞原子单腔磁光阱,本文分析并计算了磁光阱中汞原子受力情况和一维运动规律,在此基础上用随机数方法对磁光阱中汞原子三维装载进行了数值计算,获得了磁光阱中的稳态原子数,研究了磁光阱的冷却激光的光强、失谐量以及磁场梯度等参数对稳态原子数的影响,得出了获得最优装载率的实验参数.涉及的计算方法和结论对汞原子光晶格钟的实验设计具有参考价值. 相似文献
3.
E. Peik 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(2):179-183
An electrodynamic trap is proposed that stores cold neutral atoms or nonpolar molecules in their ground state as well as in
excited states by means of the quadratic Stark effect. The trap uses an oscillating hexapole field and a superposed static
homogeneous field. The dynamics of an atom in this trap can be described as a harmonic oscillation in a static pseudopotential.
Stability criteria and sample parameters for a number of atomic species are given.
Received: 7 August 1998 / Received in final form: 7 January 1999 相似文献
4.
J. Dilling J.A. Behr A. Gorelov T. Swanson O. Häusser D. Melconian K.P. Jackson M. Trinczek U. Giesen J.M. D’Auria 《Hyperfine Interactions》1998,115(1-4):159-164
Magneto optical traps (MOT) allow the cooling and storing of neutral atoms in a volume of a few cubic millimeters by use of
laser beams and a magnetic field. Such devices offer new and exciting opportunities for precision measurements of radioactive
isotopes. Here we present experiments performed with a double-MOT system coupled to the on-line separator TISOL at TRIUMF/Vancouver,
Canada. For the first time, the Β-decay of free atoms stored in such a device could be observed. We report on coincidence
measurements between beta-particles and the argon recoils in the decay of 37K and 38rm{m}}K. The charge state ratios of the recoil-ions were deduced by Time-Of-Flight separation in an acceleration field. The
final goal of those investigations is a precision test of the Standard Model by measuring the –nu-correlation parameter a.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
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
6.
7.
Doppler cooling of 88Sr atoms is studied in the presence of off-resonant red-detuned fluctuating laser fields.Using a semi-classical approach,we show that the relevant physical quantities in the cooling process,such as optical forces,the damping coefficient,Doppler temperature,and atom number in the trap,are strongly affected by the laser amplitude and phase fluctuations.We find that the Doppler cooling limit is higher than the predicted Doppler theory for non-fluctuating lasers.This ... 相似文献
8.
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
9.
Daniel Reitz Arno Rauschenbeutel 《Optics Communications》2012,285(23):4705-4708
A double-helix optical trapping potential for cold atoms can be straightforwardly created inside the evanescent field of an optical nanofiber. It suffices to send three circularly polarized light fields through the nanofiber; two counterpropagating and far red-detuned with respect to the atomic transition and the third far blue-detuned. Assuming realistic experimental parameters, the transverse confinement of the resulting potential allows one to reach the one-dimensional regime with cesium atoms for temperatures of several μK. Moreover, by locally varying the nanofiber diameter, the radius and pitch of the double-helix can be modulated, thereby opening a realm of applications in cold-atom physics. 相似文献
10.
Experiments on trapping ytterbium atoms in various optical lattices are presented. After the two-stage cooling, first in a blue magneto-optical trap and then in a green magneto-optical trap, the ultracold 171 Yb atoms are successfully loaded into one-, two-, and three-dimensional optical lattices operating at the Stark-free wavelength, respectively. The temperature, number, and lifetime of cold 171 Yb atoms in one-dimensional lattice are measured. After optimization, the one-dimensional lattice with cold 171Yb atoms is used for developing an ytterbium optical clock. 相似文献
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12.
J.H. Thywissen M. Olshanii G. Zabow M. Drndić K.S. Johnson R.M. Westervelt M. Prentiss 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,7(3):361-367
We describe how tightly confining magnetic waveguides for atoms can be created with microfabricated or nanofabricated wires.
Rubidium atoms guided in the devices we have fabricated would have a transverse mode energy spacing of K. We discuss the creation of a single-mode waveguide for atom interferometry whose depth is comparable to magneto-optical
trap (MOT) temperatures. We also discuss the application of microfabricated waveguides to low-dimensional systems of quantum
degenerate gases, and show that confinement can be strong enough to observe fermionization in a strongly interacting bosonic
ensemble.
Received 1st December 1998 and Received in final form 23 February 1999 相似文献
13.
提出了一种利用单光束照明二元π相位板与透镜组合系统实现冷原子或冷分子囚禁的可控制光学四阱新方案.计算了四阱的光强分布,讨论了从光学四阱到双阱或到单阱的演化过程,并导出了四阱和双阱几何参数、光强分布、强度梯度及其曲率与光学透镜系统参数间的解析关系.研究表明,通过相对移动二元π相位板可实现光学四阱到双阱或到单阱的连续双向演化,获得了四阱或双阱间距与相位板移动距离的关系.该方案在超冷原子物理、冷分子物理、原子光学、分子光学和量子光学,甚至量子计算及信息处理等领域中有着广阔的应用前景.
关键词:
二元π相位板
可控制光学四阱
原子分子囚禁
原子光学 相似文献
14.
An optical atomic clock with 171Yb atoms is devised and tested. By using a two-stage Doppler cooling technique, the 171Yb atoms are cooled down to a temperature of 6 ± 3 μK, which is close to the Doppler limit. Then, the cold 171Yb atoms are loaded into a one-dimensional optical lattice with a wavelength of 759 nm in the Lamb-Dicke regime. Furthermore, these cold 171Yb atoms are excited from the ground-state 1S0 to the excited-state 3P0 by a clock laser with a wavelength of 578 nm. Finally, the 1S0-3P0 clock-transition spectrum of these 171Yb atoms is obtained by measuring the dependence of the population of the ground-state 1S0 upon the clock-laser detuning. 相似文献
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16.
提出了一种采用单光束照明二元π相位板与透镜组合系统产生的适用于冷原子与分子囚 禁的可控制光学双阱方案.计算了双阱的光强分布,研究了双阱到单阱的演化过程,并导出了双阱几何参数、光强分布、强度梯度及其曲率与光学系统参数间的解析关系.研究发现, 通过相对移动二元相位板可实现光学双阱到单阱的连续双向演化,得到了双阱间距与相位板移动距离的关系.该方案不仅简单可行、操作方便,而且在原子物理、原子光学、分子光学和量子光学领域中有着广阔的应用前景.
关键词:
二元相位板
可控制光学双阱
原子囚禁
原子光学
分子光学 相似文献
17.
R. Chicireanu Q. Beaufils A. Pouderous B. Laburthe-Tolra É. Maréchal L. Vernac J.-C. Keller O. Gorceix 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,45(2):189-195
We report the fast accumulation of a large number of
metastable 52Cr atoms in a mixed trap, formed by the
superposition of a strongly confining optical trap and a quadrupolar
magnetic trap. The steady state is reached after about 400 ms,
providing a cloud of more than one million metastable atoms at a
temperature of about 100 μK, with a peak density of 1018
atoms m-3. We have optimized the loading procedure, and
measured the light shift of the 5D4 state by analyzing how the
trapped atoms respond to a parametric excitation. We compare this
result to a theoretical evaluation based on the available
spectroscopic data for chromium atoms. 相似文献
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20.
Xiao-Feng Shi 《Frontiers of Physics》2021,16(5):52501
Alkaline-earth-like (AEL) atoms with two valence electrons and a nonzero nuclear spin can be excited to Rydberg state for quantum computing. Typical AEL ground states possess no hyperfine splitting, but unfortunately a GHz-scale splitting seems necessary for Rydberg excitation. Though strong magnetic fields can induce a GHz-scale splitting, weak fields are desirable to avoid noise in experiments. Here, we provide two solutions to this outstanding challenge with realistic data of well-studied AEL isotopes. In the first theory, the two nuclear spin qubit states |0〉 and |1〉 are excited to Rydberg states |r〉 with detuning Δ and 0, respectively, where a MHz-scale detuning Δ arises from a weak magnetic field on the order of 1 G. With a proper ratio between Δ and Ω, the qubit state |1〉 can be fully excited to the Rydberg state while |0〉 remains there. In the second theory, we show that by choosing appropriate intermediate states a two-photon Rydberg excitation can proceed with only one nuclear spin qubit state. The second theory is applicable whatever the magnitude of the magnetic field is. These theories bring a versatile means for quantum computation by combining the broad applicability of Rydberg blockade and the incomparable advantages of nuclear-spin quantum memory in two-electron neutral atoms. 相似文献