1 中国科学院上海光学精密机械研究所航天激光工程部，上海 201800
2 中国科学院上海光学精密机械研究所量子光学重点实验室，上海 201800
3 中国科学院大学，北京 100049
在各向同性激光冷却原子实验中，光场分布是影响冷原子分布的重要因素，可以利用真空腔的结构和激光的注入方式的不同来调控腔内的冷原子分布。本文提出了一种扁平形漫反射腔体结构，并对冷却光的不同注入方式和不同尺寸的腔体结构形成的光场分布进行了仿真。仿真结果表明，与自由空间光入射相比，激光由光纤入射能够获得更均匀的准二维分布的光场，因此可以通过调节光纤的入射角度及光纤参数，实现对光场均匀度的优化。此外，随着腔体边长的等比放大，腔内光功率密度呈负指数幂衰减。扁平形漫反射腔形状接近二维，在准二维分布的光场和特殊的扁平形腔体结构的作用下，能够获得呈准二维分布的冷原子，在量子传感及量子精密测量领域具有重要的应用前景。
光场仿真 漫反射 准二维光场 各向同性激光冷却
Author Affiliations
Abstract
1 China University of Petroleum, Qingdao 266580, China
2 Beijing Institute of Technology, Beijing 100081, China
We developed a general framework for parallel all-optical logic operations with independent phase control of arbitrary orthogonal polarization state enabled by a single-layer metasurface. A pair of orthogonal circular polarized bases are used as two input channels of the logic operator, and their four combinations perfectly match various binary input states. Correspondingly, distinct phase profiles are encoded into the metasurface, which enables parallel operation of the two logic gates by way of polarization switching. It allows for an efficient and compact way to implement multi-channel multiplexed logic gate operations with the capability of fast optical computing at the chip scale.
parallel all-optical logic operation metasurface polarization Chinese Optics Letters
2023, 21(10): 101602
1 中国科学院上海光学精密机械研究所航天激光工程部，上海 201800
2 中国科学院大学材料科学与光电子技术学院，北京 100049
3 电子科技大学电子科学与工程学院，四川 成都 611731
4 中国科学院上海光学精密机械研究所量子光学重点实验室，上海 201800
射频蒸发冷却作为获取超冷原子简并量子气体的手段之一，对玻色-费米协同冷却的实现至关重要。为了在空间站上实现超冷量子简并气体，设计了一种特殊的射频天线。该天线被置于一个冷原子实验用真空腔内，与腔上集成的冷却、探测、光阱、磁阱、光晶格、Feshbach磁场等装置一同组成了通用型超冷原子物理实验系统，该实验系统满足载人航天工程在尺寸、重量、功耗、可靠性和电磁兼容性等方面的严格要求。利用有限元仿真方法对天线进行设计和评估，并在地面实验平台上对其各项性能指标进行测试和实验验证。结果表明，本设计除了能够降低90%的射频功率需求外，还能维持科学腔的超高真空水平，并具备良好的电磁兼容性，符合载人航天工程的要求。
量子光学 玻色-爱因斯坦凝聚体 射频诱导蒸发冷却 微波 Zeeman效应
1 中国科学院上海光学精密机械研究所量子光学重点实验室，上海 201800
2 中国科学院上海光学精密机械研究所航天激光工程部，上海 201800
3 中国科学院大学材料科学与光电技术学院，北京 101408
介绍了一种应用于空间超冷原子物理实验平台的二维磁光阱光机系统的集成优化设计方法，可获得高通量冷原子束流以满足后续三维磁光阱中冷原子的高装载率。二维磁光阱激光系统的主要光路包括冷却光、重泵光、推送光和缓冲光。首先，利用Zemax软件对光学系统进行设计和优化，使得成像系统的点列图均方根(RMS)半径均小于艾里斑，而且光学系统的调制传递函数(MTF)与衍射极限传递函数非常接近，系统具备优良的光学性能。在此基础上，利用Solidworks软件仿真完成了高稳定度、简单化、小型化光机结构的设计。针对4路光同时输入一个光机口的难题，提出了V-GROOVE光纤设计方案，进一步提高了所有光机组件的集成度。该系统在工程化的基础上实现了装载率约为1.89×108 /s的连续冷原子束流。
量子光学 二维磁光阱 激光冷却 原子装载 Zemax软件 Solidworks软件 中国激光
2022, 49(11): 1112001
Author Affiliations
Abstract
1 Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201 800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
The environmental perturbation on atoms is a key factor restricting the performance of atomic frequency standards, especially in the long-term scale. In this Letter, we perform a real-time noise distinguish (RTND) to an atomic clock to decrease the uncertainty of the atomic clock beyond the level that is attained by the current controlling method. In RTND, the related parameters of the clock are monitored in real time by using the calibrated sensors, and their effects on the clock frequency are calculated. By subtracting the effects from the error signal, the local oscillator is treated as equivalently locked to the unperturbed atomic levels. In order to perform quantitative tests, we engineer time-varying noise much larger than the intrinsic noise in our fountain atomic clock. By using RTND, the influences of the added noises are detected and subtracted precisely from the error signals before feeding back to the reference oscillator. The result shows that the statistical uncertainty of our fountain clock is improved by an order of magnitude to 2×10?15. Besides, the frequency offset introduced by the noise is also corrected, while the systematic uncertainty is unaffected.
020.1335 Atom optics 120.3940 Metrology Chinese Optics Letters
2017, 15(5): 050201
Author Affiliations
Abstract
1 Key Laboratory of Quantum Optics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
A self-comparison method with closely interleaved switching states is analyzed and used to evaluate some type-B uncertainties of an Rb87 atomic fountain clock. Free from additional frequency reference, the method can be applied to a running fountain to reach a precision beyond its uncertainty. A verification experiment proves an uncertainty of 9.2×10 16 at an averaging time of 242500 s. Further, the method is applied to measure light shift, and no visible relative frequency shift is found in the fountain within the uncertainty of 2.1×10 15. When applied to the evaluation of a cold collisional shift, the result gives a 2.2×10 15 shift with a 9.5×10 16 uncertainty.
020.1335 Atom optics 120.3940 Metrology Chinese Optics Letters
2016, 14(8): 081201
Author Affiliations
Abstract
1 Key Laboratory of Quantum Optics, Center for Cold Atom Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Science, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
We report a locking mode in which the local oscillator (LO) is locked to an atomic fountain and calibration of the residual frequency drift (RFD). In this running mode, the locked LO outputs a standard frequency signal, and a short-term fractional frequency stability of 2.7×10 13τ 1/2 is achieved. Due to the frequency drift of the LO in free running mode, a systematic frequency bias, or RFD, exists after being locked by the atomic fountain. We analyze and measure the RFD with a value of 3(2)×10 16. A sectionalized post-process method is adopted to calibrate the RFD.
120.0120 Instrumentation, measurement, and metrology 270.0270 Quantum optics 120.3940 Metrology Chinese Optics Letters
2015, 13(9): 091201
