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1.
We experimentally demonstrate a controllable electrostatic beam splitter for guided ND3 molecules with a single Y-shaped charged wire and a homogeneous bias field generated by a charged metallic parallel-plate capacitor. We study the dependences of the splitting ratio R of the guided ND3 beam and its relative guiding efficiency η on the voltage difference between two output arms of the splitter. The influences of the molecular velocity v and the cutting position L on the splitting ratio R are investigated as well, and the guiding and splitting dynamic processes of cold molecules are simulated. Our study shows that the splitting ratio R of our splitter can be conveniently adjusted from 10% to 90% by changing ΔU from -6 kV to +6 kV, and the simulated results are consistent with our experimental ones. 相似文献
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Sheng-Qiang Li 《Chinese Journal of Physics (Taipei)》2018,56(5):2605-2612
A spatial electrostatic beam splitter composed of six charged poles for polar molecules in weak-field-seeking states is proposed. First, the schematic diagram is given. With the help of finite element software the spatial distribution of the electrical field is calculated. The dynamic process of the loading and splitting polar molecules is simulated using the classical Monte Carlo method. The influences of the longitudinal velocity of the incident molecular beam and the voltages on the loading efficiency are studied. Two output arms of the beam splitter can be cut off at a certain position to adjust the splitting ratio of the molecular beam. Then the influences of the voltages and cutting positions on the splitting ratio are investigated. The results indicate that the splitting ratio can be manipulated conveniently from 0% to 100%. 相似文献
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Electrostatic guiding of cold polar molecules on a chip 总被引:1,自引:0,他引:1
We propose a novel scheme to guide cold polar molecules on the surface of an insulating substrate (i.e. a chip) using an electrostatic field generated by the combination of a pair of parallel charged wires and a grounded metal plate. The spatial distributions of the electric fields from the above charged-wire layout and their Stark potentials for cold CO molecules and dipole forces are calculated, and the relationships between the electric field and the geometric parameters of our charged-wire system are analyzed. Our study shows that our charged-wire scheme can be used to guide cold polar molecules in the weak-field-seeking state, and to construct various molecular optical elements, such as a molecular funnel, a molecular beam splitter and a molecular interferometer and so on, to form various integrated molecular optical elements and their molecular chips, and even to generate a continuous wave (CW) cold molecular beam by using a low-pass energy filter based on bent two-wire guiding. 相似文献
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提出一种使用带电金属环和六个球电极和一个外加偏置电场实现对冷极性分子静电囚禁的新方案.计算装载和囚禁时空间电场分布.囚禁中心距离芯片表面的高度可以通过外电场和环形电极所加电压来操控.蒙特卡罗模拟表明对于中心速度为15 m·s-1的ND3分子束,装载效率可以达到70%,得到冷分子的温度大约为45 mK.当继续增加偏置电场强度时,单阱分裂为对称的两个阱.如果同时改变球形电极上所加电压,得到不对称的两个阱,可以借此来调节两个阱中所囚禁的冷分子数目的比例.为了易于理解,用蒙特卡罗方法模拟了装载、囚禁、分裂冷分子波包的动力学过程. 相似文献
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We propose a novel scheme in which cold polar molecules are trapped
by an electrostatic field generated by the combination of a pair of
parallel transparent electrodes (i.e., two infinite transparent
plates) and a ring electrode (i.e., a ring wire). The spatial
distributions of the electrostatic fields from the above charged wire
and the charged plates and the corresponding Stark potentials for
cold CO molecules are calculated; the dependences of the trap centre
position on the geometric parameters of the electrode are analysed.
We also discuss the loading process of cold molecules from a cold
molecular beam into our trap. This study shows that the proposed
scheme is not only simple and convenient to trap, manipulate and
control cold polar molecules in weak-field-seeking states, but also
provides an opportunity to study cold collisions and collective
quantum effects in a variety of cold molecular systems, etc. 相似文献
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提出了采用双环形载荷导线和两透明电极系统实现冷分子静电囚禁的可控制静电双阱的新方案,计算了带电圆导线和带电板所产生的静电场分布,从几个方面分析了这个囚禁方案的优点. 提出了一种有效的冷分子装载方法,并研究了双阱到单阱的演化过程. 研究表明,该可控制静电双阱方案不仅方便装载与操控弱场搜寻态的极性冷分子,而且在分子物质波的干涉、纠缠、冷碰撞,甚至进行双阱分子BEC研究等分子光学领域中有着广阔的应用前景.
关键词:
极性冷分子
静电囚禁
可控制静电双阱
分子光学 相似文献
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提出了一种采用二元π位相板与柱面透镜组合而构成表面光波导型原子(或分子)分束器及其Mach-Zehnder干涉仪与X-分束器列阵的新方案,介绍了本方案的物理思想与基本原理,导出了光强分布、强度梯度、分束距离和分束路径的宽度与光学系统参数间的解析关系,并分析和讨论了本方案的潜在应用及其可行性. 研究表明,本方案设计新颖、光路简单,便于与其他元件组合构成具有表面微结构的集成原子(或分子)光学元器件及其全光型原子(或分子)芯片.
关键词:
原子(或分子)光波导
原子(或分子)分束器
原子(或分子)芯片
二元π位相板 相似文献
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本文建立了外加电场调制二维六角位相阵列光分束器的倒格矢理论模型, 利用数值模拟方法开展了阵列光分束器的理论研究, 对可调位相差阵列光分束器进行了分析, 得到了不同分数泰伯距离以及外加电场条件下的光强分布图. 实验设计与制备了铌酸锂二维六角位相阵列光分束器, 并对其进行了Talbot衍射光分束实验研究, 当外加电压为0.5 kV(电场为1 kV/mm)时, 观测到了Talbot衍射光分束现象, 随着外加调制电场的增大, 其衍射光分束图像越清晰, 该实验结果和理论研究结果相符. 相似文献
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Stark-potential evaporative cooling of polar molecules in a novel optical-access opened electrostatic trap 下载免费PDF全文
《中国物理 B》2015,(11)
We propose a novel optical-access opened electrostatic trap to study the Stark-potential evaporative cooling of polar molecules by using two charged disk electrodes with a central hole of radius r0= 1.5 mm, and derive a set of new analytical equations to calculate the spatial distributions of the electrostatic field in the above charged-disk layout. Afterwards, we calculate the electric-field distributions of our electrostatic trap and the Stark potential for cold ND3 molecules, and analyze the dependences of both the electric field and the Stark potential on the geometric parameters of our charged-disk scheme,and find an optimal condition to form a desirable trap with the same trap depth in the x, y, and z directions. Also, we propose a desirable scheme to realize an efficient loading of cold polar molecules in the weak-field-seeking states, and investigate the dependences of the loading efficiency on both the initial forward velocity of the incident molecular beam and the loading time by Monte Carlo simulations. Our study shows that the maximal loading efficiency of our trap scheme can reach about 95%, and the corresponding temperature of the trapped cold molecules is about 28.8 m K. Finally, we study the Stark-potential evaporative cooling for cold polar molecules in our trap by the Monte Carlo method, and find that our simulated evaporative cooling results are consistent with our developed analytical model based on trapping-potential evaporative cooling. 相似文献
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A novel implementation of a dispersion-based beam splitter in a photonic crystal (PhC) is proposed. The beam splitter consists of two periodic structures: a nonchannel dispersion-guiding region and a splitting structure operating inside the photonic bandgap. The dispersion-guiding PhC structure is used to route the optical wave by exploiting the dispersion properties of the lattice. An arbitrary power ratio between the output beams can be achieved by varying the parameters of the splitting structure. Within the studied range of splitting structures, high output power was observed and verified experimentally. 相似文献
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GL Gattobigio A Couvert G Reinaudi B Georgeot D Guéry-Odelin 《Physical review letters》2012,109(3):030403
We study experimentally and theoretically a beam splitter setup for guided atomic matter waves. The matter wave is a guided atom laser that can be tuned from quasimonomode to a regime where many transverse modes are populated, and propagates in a horizontal dipole beam until it crosses another horizontal beam at 45°. We show that depending on the parameters of this X configuration, the atoms can all end up in one of the two beams (the system behaves as a perfect guide switch), or be split between the four available channels (the system behaves as a beam splitter). The splitting regime results from a chaotic scattering dynamics. The existence of these different regimes turns out to be robust against small variations of the parameters of the system. From numerical studies, we also propose a scheme that provides a robust and controlled beam splitter in two channels only. 相似文献
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Deyang Duan Shaojiang Du Li Yan Shengshan Jiang Yuanyuan Liu Lu Zhang Yunjie Xia 《中国光学快报(英文版)》2014,12(7):72701-66
In this letter, we analyze the effects of light intensity find that the brightness of reflective ghost image can on reflective ghost imaging with thermal source. We be changed by modulating the light intensity of the source and the splitting ratio of the beam splitter. The signal-to-noise ratio will be improved by increa.sing the light intensity of the source. More important, we can obtain the reflective ghost image with high image quality by adopting a low light intensity signal beam and a high light intensity reference beam, which is better than the classical optical imaging, because it can reduce the effects of light on the object. 相似文献
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Xiao Y Klein M Hohensee M Jiang L Phillips DF Lukin MD Walsworth RL 《Physical review letters》2008,101(4):043601
We demonstrate a slow light beam splitter using rapid coherence transport in a wall-coated atomic vapor cell. We show that particles undergoing random and undirected classical motion can mediate coherent interactions between two or more optical modes. Coherence, written into atoms via electromagnetically induced transparency using an input optical signal at one transverse position, spreads out via ballistic atomic motion, is preserved by an antirelaxation wall coating, and is then retrieved in outgoing slow light signals in both the input channel and a spatially-separated second channel. The splitting ratio between the two output channels can be tuned by adjusting the laser power. The slow light beam splitter may improve quantum repeater performance and be useful as an all-optical dynamically reconfigurable router. 相似文献
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Theoretical derivation and simulation of a versatile electrostatic trap for cold polar molecules 下载免费PDF全文
We propose a versatile electrostatic trap scheme using several charged spherical electrodes and a bias electric held.We hrst give the two-ball scheme and derive the analytical solution of the electric held.In order to make a comparison,we also give the numerical solution calculated by the hnite element software(Ansoft Maxwell).Considering the loading of cold polar molecules into the trap,we give the three-ball scheme.We hrst give the analytical and numerical solutions of the distribution of the electric held.Then we simulate the dynamic process of the loading and trapping cold molecules using the classical Monte Carlo method.We analyze the influence of the velocity of the incident molecular beam and the loading time on the loading efficiency.After that,we give the temperature of the trapped cold molecules.Our study shows that the loading efficiency can reach 82%,and the corresponding temperature of the trapped molecules is about 24.6 mK.At last,we show that the single well divides into two ones by increasing the bias electric held or decreasing the voltages applied to the spherical electrodes. 相似文献
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We propose a novel scheme to guide cold polar molecules on the surface of an insulating substrate (i.e., a chip) using a static electric field generated by the combination of a pair of parallel charged wires and a grounded metal plate. We calculate the spatial distributions of the electric fields from the above chargedwire layout and their Stark potentials for cold CO molecules, and analyze the relationships between the electric field and the parameters of the charged-wire layout. The result shows that this charged-wire scheme can be used to guide cold polar molecules in the weak-field-seeking state and to form various molecule-optical elements, even to realize a single-mode molecular waveguide on a molecule chip under certain conditions. 相似文献
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针对传统偏振分束器窄波段、窄角度范围的不足,研制了一种在宽波段宽角度范围内具有180°分光功能的偏振分束器/耦合器。该器件基于线栅偏振器和亚波长光栅结构原理设计,利用半导体工艺的刻蚀技术制作。利用一维金属线栅对入射电磁波的偏振响应和亚波长光栅仅存在零级衍射的特性,实现了较宽的通带宽度与可接受角度范围、极大的分光角度、高消光比和低插入损耗。实验测得透射、反射消光比均大于20 dB,插入损耗小于0.5dB。通过自行搭建的微结构测试平台,测量了p、s光的透射率、反射率随入射角度变化的曲线,和严格耦合波理论模拟结果符合。深入分析了制作中的过刻蚀对性能产生的影响。 相似文献