排序方式: 共有70条查询结果,搜索用时 15 毫秒
51.
Effects of the Scattering Length on the Yrast Spectrum for a Two-Component Bose-Einstein Condensates
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We study the energy eigenvalue and the yrast states for a harmonically two-component weak-interacting Bose-Einstein condensate (BEC) when the intra-species and interspecies scattering length are different. The energy shift for different energy eigenvalues related to intra-and interspecies scattering lengths is calculated with the perturbation method. The actual yrast spectrum is more complicated than that when intra-species and interspecies scattering length are equal. The degenerated features disappear and so do the perfect symmetric features. 相似文献
52.
2001 年,瑞典皇家科学院宣布2001 年诺贝尔物理学奖分别授予美国科学家埃里克·康奈尔(Eric Cornell)、德国科学家沃尔夫冈·克特勒(Wolfgang Ketterle),以及美国科学家卡尔·韦曼(Carl Wieman)。 相似文献
53.
54.
In this paper, we first present a full numerical simulation for the trapping and retrieval procedure of eight continuing "1" Guassian pulses (i.e., "11111111") in the electromagnetically induced transparency (BIT) medium. This simulation shows that an BIT medium has the ability to store multiple light pulses in a shape-preserving way. And we also, for the first time, give the formula evaluating the maximum number of pulses that can be stored by an EIT medium at one time. This work reveals a new possible way to the reversible storage of the photonic information. 相似文献
55.
原子的激光冷却与捕陷(Ⅱ) 总被引:1,自引:0,他引:1
三、原子束的激光准直 上述激光减速原子束方法并不能得到很窄的原子束.相反,在减速途径上原子束会不断扩束.其原因:一是从束源出发时原子束总有原始发散角,束截面随路程增大;二是减速过程存在着横向加热效应.我们说原子在减速过程中因吸收反向光子而损失动量,而在各向同性的自发辐射中动量变化为零,这是统计平均的结果.”实际上每次具体发射时原子还是有动量变化的.这种变化的轴向分量最终导致纵向速率涨落,而横向分量会无规则地不断积累,最后使原子获得一平均横向速度υ.这就是横向加热.设减速过程中发生了n次吸收和发射光子的元动作,则为… 相似文献
56.
57.
Matter-wave interferometers with spin quantum states are attractive in quantum manipulation and precision measurements. Here, five spatial interference patterns corresponding to the full spin states are observed in each run of the experiment, by the combination of the Majorana transition according to the exponential modulation of the magnetic field pulse decline curve and radio frequency coupling among multiple magnetic sub-states.Compared to the realization of two Majorana transitions, the interference fringe for the magnetic field insensitive state also has a higher contrast. After spatially overlapping the full magnetic sub-state interference patterns dozens of times in consecutive experimental measurements, clear fringes are still observed, indicating the great stability of the relative phases of different components. This indicates the potential to achieve an interferometer with multiple spin clocks. 相似文献
58.
We propose, design, and realize a compact stabilized laser system that can be tuned within 24 GHz automatically.This laser system consists of two distributed feedback(DFB) lasers, one of which is reference and locked to the D2 line of ~(87)Rb, the other laser is a slave that is locked to the reference laser via a loop servo. We measured the frequency of the beating signal of the two lasers and generated an error signal, which controlled the frequency of the slave laser to close the loop. We compressed the fluctuation of the beating signal's frequency to less than 1 MHz.Furthermore, the system can also automatically determine and control whether the slave is red detuned or blue detuned to the reference. The dimensions of our laser system are about 15 cm × 20 cm × 10 cm. This kind of laser system can be applied in many important applications, such as atomic interferometer and cold atomic clock. 相似文献
59.
We performed an experimental study on the dependence of the linewidth of electromagetically induced transparency (EIT) on the temperature of medium in a Λ-type configuration using caesium vapour. We found that the transparent window is narrowed in the EIT whose two ground levels are composed of two hyperfine levels, and broadened in the case when the two ground levels are degenerated Zeeman sublevels, as the temperature of vapour cell is increased. The explanation for the phenomena is given qualitatively. 相似文献
60.
Observation of Two-Dimensional Mott Insulator and π-Superfluid Quantum Phase Transition in Shaking Optical Lattice
下载免费PDF全文
![点击此处可从《中国物理快报》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The Mott insulator and superfluid phase transition is one of the most prominent phenomena in ultracold atoms. We report the observation of a novel 2D quantum phase transition between the Mott insulator and πsuperfluid in a shaking optical lattice. In the deep optical lattice regime, the lowest S band can be tuned to Mott phase, while the higher Px,y bands are itinerant for having larger bandwidth. Through a shaking technique coupling the s-orbital to px,y-orbital states, we experimentally observ... 相似文献