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《中国光学快报(英文版)》2017,(4)
The construction of a two-dimensional magneto–optical trap with hollow cooling and pushing(2D-HP MOT) is reported in detail,and a velocity-tunable cold atomic beam produced by this 2D-HP MOT is demonstrated.The magneto–optical trap system,which is constructed by a transparent quartz tube,is low in price,easy to fabricate and assemble,and convenient for atomic trapping and detection.The mean axial velocity of the cold atomic beam can be tuned from 4.5 to 8 m/s,while the atomic flux remains at a level of 10~(10) atoms∕s.This cold atomic beam source can be applied in the areas of high-precision measurements based on cold atoms. 相似文献
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A continuous cold atomic beam from a magneto-optical trap 总被引:3,自引:0,他引:3
L. Cacciapuoti A. Castrillo M. de Angelis G.M. Tino 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,15(2):245-249
We have developed and characterized a new method to produce a continuous beam of cold atoms from a standard vapour-cell magneto-optical
trap (MOT). The experimental apparatus is very simple. Using a single laser beam it is possible to hollow out in the source
MOT a direction of unbalanced radiation pressure along which cold atoms can be accelerated out of the trap. The transverse
cooling process that takes place during the extraction reduces the beam divergence. The atomic beam is used to load a magneto-optical
trap operating in an ultra-high vacuum environment. At a vapour pressure of 10-8mbar in the loading cell, we have produced a continuous flux of 7×107atoms/s at the recapture cell with a mean velocity of 14 m/s. A comparison of this method with a pulsed transfer scheme is
presented.
Received 19 February 2001 相似文献
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A compact cold atom beam source based on a multistage two-dimensional magneto-optical trap (MOT) has been demonstrated and characterized. The multiple-stage design greatly reduces the overall size of the source apparatus while providing a high flux of atoms. The cold atom beam was used to load a separate MOT in ultrahigh vacuum, and we obtained an actual trap loading rate of 1.5 x 109 atoms/s while using only 20 mW of total laser power for the source. The entire source apparatus, including optics, can fit into a 4 cm x 4 cm x 13 cm volume. 相似文献
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Atomic beam guide by a one-dimensional magneto-optical trap 总被引:1,自引:0,他引:1
An atomic beam has been collimated, compressed, and deflected simultaneously by an atomic beam guide based on an inclined
one-dimensional magneto-optical trap (1D-MOT). Isotope-selected rubidium atoms were extracted from the naturally-mixed thermal
atomic beam with this method. We could manipulate the transverse displacement of the deflected beam precisely by adjusting
the current in the copper rods to generate the quadrupole magnetic field. We could extract more than 50% of the incident atoms
as a deflection beam when we combined this deflection technique with the atomic deceleration using a broadband spectral light.
Received: 10 December 1998 / Published online: 24 June 1999 相似文献
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Focusing of an atomic beam by a Fresnel atom microlens formed by an optical field diffracted by an aperture whose size is comparable to or greater than the radiation wavelength is considered. It is shown that the dipole gradient force enables one to focus the atomic beam to a spot of about 10 nm in diameter. The focusing properties of a Fresnel atom microlens are analyzed within a model describing the dipole interaction of rubidium atoms with monochromatic radiation near the D-line. 相似文献
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通过分析铯原子在σ~+-σ~-组态的圆偏振光照射下塞曼子能级的分布情况,构造铯原子在二维磁光阱(2D-MOT)中的受力模型,利用龙格-库塔方法求解铯原子的运动方程,实现原子束产生过程的三维模拟.得出原子束流量随小孔半径、铯原子蒸汽压、激光光强、激光失谐量、磁场梯度等的变化规律.与实验数据进行比较表明受力模型的正确性,该方法能直观模拟原子束的产生,准确揭示原子束流量随各项参数的变化规律,为实验提供理论指导. 相似文献
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通过分析铯原子在σ+-σ-组态的圆偏振光照射下塞曼子能级的分布情况,构造铯原子在二维磁光阱(2D-MOT)中的受力模型,利用龙格-库塔方法求解铯原子的运动方程,实现原子束产生过程的三维模拟。得出原子束流量随小孔半径、铯原子蒸汽压、激光光强、激光失谐量、磁场梯度等的变化规律。与实验数据进行比较表明受力模型的正确性, 该方法能直观模拟原子束的产生,准确揭示原子束流量随各项参数的变化规律,为实验提供理论指导。 相似文献
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The instabilities observed in the atomic cloud of a magneto-optical trap are experimentally studied through the dynamics of the center of mass location and the cloud population. Two dynamical components are identified: a slow, stochastic one affects both variables, and a fast, deterministic one affects only the center of mass location. A one-dimensional stochastic model taking into account the shadow effect is developed from these observations and reproduces the experimental behavior. It is shown that instabilities are driven by noise and present stochastic resonancelike characteristics. 相似文献
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《中国光学快报(英文版)》2016,(4)
We demonstrate a magneto-optical trap(MOT) with counter-propagating two-color cooling b('ams in a cesium6S1/2 — 6P3/2 — 8S!/2(852.3 + 794.6 nm) atomic system. Based on the conventional MOT due entirely to the852.3 nm cooling laser5 s scattering forces, we replace one of the six 852.3 inn cooling beams witli a 794.6 11111 cooling beam. Our two-color MOT can efficiently cool and trap atoms from the red to blue detuning sides of two-photon resonance without pre-cooling. The technique is promising for the direct generation of correlated photon pairs in a two-color MOT based on diamond-configuration four-wave mixing. 相似文献
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We demonstrate the fast accumulation of 52Cr atoms in a conservative potential from a guided atomic beam. Without laser cooling on a cycling transition, a dissipative step involving optical pumping allows us to load atoms at a rate of 2×10(7) s(-1) in the trap. Within less than 100 ms we reach the collisionally dense regime, from which we produce a Bose-Einstein condensate with subsequent evaporative cooling. This constitutes a new approach to degeneracy where Bose-Einstein condensation can be reached without a closed cycling transition, provided that a slow beam of particles can be produced. 相似文献
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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
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We report the first observation of a nondipole transition in an ultracold atomic vapor. We excite the 3P-4P electric quadrupole (E2) transition in 23Na confined in a magneto-optical trap, and we demonstrate its application to high-resolution spectroscopy by making the first measurement of the hyperfine structure of the 4P(1/2) level and extracting the magnetic dipole constant A=30.6+/-0.1 MHz. We use cw optical-optical double resonance accompanied by photoionization to probe the transition. 相似文献
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We demonstrate a new type of high-resolution two-photon frequency modulation (FM) spectroscopy with cold atoms in a magneto-optical trap. Instead of modulating the probe as in ordinary FM spectroscopy, we modulate the trap itself by FM of the trapping beams. We present theoretical as well as experimental results for both absorption and polarization rotation spectroscopy. Finally, we demonstrate two-photon FM spectroscopy, using the intrinsic phase noise of the trapping diode lasers. 相似文献
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V. S. Alexandrov G. G. Gulbekian N. Yu. Kazarinov 《Physics of Particles and Nuclei Letters》2010,7(7):543-547
To increase the intensity of an ion beam injected in a cyclotron, the possibility of focusing by an axial potential electrode
is investigated. The influence of the electric field of an electrode on the beam emittance and that of particle losses on
an electrode are estimated. The results of our numerical simulation are compared with theoretical estimations. 相似文献
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We have observed self-sustained radial oscillations in a large magneto-optical trap, containing up to 10(10) Rb85 atoms. This instability is due to the competition between the confining force of the magneto-optical trap and the repulsive interaction associated with multiple scattering of light inside the cold atomic cloud. A simple analytical model allows us to formulate a criterion for the instability threshold, in fair agreement with our observations. This criterion shows that large numbers of trapped atoms N>10(9) are required to observe this unstable behavior. 相似文献
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This paper presents an experimental demonstration of light-induced
evaporative cooling in a magneto-optical trap. An additional laser
is used to interact with atoms at the edge of the atomic cloud in
the trap. These atoms get an additional force and evaporated away
from the trap by both the magnetic field and laser fields. The
remaining atoms have lower kinetic energy and thus are cooled. It
reports the measurements on the temperature and atomic number after
the evaporative cooling with different parameters including the
distance between the laser and the centre of the atomic cloud, the
detuning, the intensity. The results show that the light-induced
evaporative cooling is a way to generate an ultra-cold atom source. 相似文献