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Jingbiao Chen – 1st expert on this subject based on the ideXlab platform
Experimental study of a miniaturized calcium Atomic Beam tube for small optical frequency standard2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF IFCS), 2017Co-Authors: Haijun Chen, Haosen Shang, Shengnan Zhang, Shunlu Xiao, Jingbiao ChenAbstract:
With the advantage of relatively simple structure, the optical frequency standard based on calcium thermal Atomic Beam has the potential to be miniaturized and engineered. We develop a new fully vacuum-sealed calcium Atomic Beam tube, which divergence angle of calcium Atomic Beam is narrower and background noise of 423 nm laser-induced fluorescence is much lower than its predecessor. This paper describes experimental study of this new tube using the 657 nm clock transition laser and 423 nm detection laser.
A transportable calcium Atomic Beam optical clock2016 IEEE International Frequency Control Symposium (IFCS), 2016Co-Authors: Xiaogang Zhang, Shengnan Zhang, Zhaojie Jiang, Min Li, Haosen Shang, Fei Meng, Wei Zhuang, Aimin Wang, Jingbiao ChenAbstract:
Achievement on Atomic optical clock, which has reached to 10-18 level uncertainty, accelerates the research of the fundamental physics. But enormous volume size limits the application of optical clock outside the lab. Here, we report a transportable Calcium Atomic Beam optical clock with higher stability than general microwave clocks. In this system, we use the electron-shelving method to greatly improve the signal-to-noise of 657 nm signal. After locking, the stability of transportable Calcium Atomic Beam optical clock is 3.0 × 10-14 at 1 s and decreases to 2.9 × 10-15 at 200 s with continuous working time 11000 s by self-evaluation. Then we have used a 750 MHz repetition frequency optical frequency comb to transfer Calcium Atomic Beam optical clock frequency to microwave and compare with Hydrogen maser. The frequency stability of Calcium Atomic Beam optical clock versus hydrogen maser reaches to 1.62 × 10-12 at 1 s, which is close to the frequency stability of Hydrogen maser. The whole system is specially designed for robustness. Besides, a new full-sealed Calcium Atomic Beam vacuum system without flanges is constructed.
Study of a fully vacuum-sealed calcium Atomic Beam tube for optical frequency standard2016 IEEE International Frequency Control Symposium (IFCS), 2016Co-Authors: Haijun Chen, Xiaogang Zhang, Shengnan Zhang, Youhuan Liang, Jianqing Yang, Jinjun Feng, Jingbiao ChenAbstract:
Optical frequency standard is regarded as the future quantum frequency standard. With no laser cooling system, the calcium Atomic Beam optical frequency standard has the potential to be miniaturized and engineered, while providing a better performance than cesium clock and hydrogen clock. This paper presents the design and fabrication of a fully vacuum-sealed calcium Beam tube with a smaller size and lighter weight. So far one testing has operated continuously for more than 15 months. We believe this study has laid a foundation for practicability and engineering of the calcium Atomic Beam optical frequency standard.
Sung Hoon Yang – 2nd expert on this subject based on the ideXlab platform
Generation of a slow and continuous cesium Atomic Beam for an Atomic clockJournal of The Optical Society of America B-optical Physics, 2002Co-Authors: Sang Eon Park, Taeg Yong Kwon, Eun-joo Shin, Sung Hoon YangAbstract:
A thermal Atomic Beam from a cesium oven was slowed down by use of the Hoffnagle modified white-light cooling technique. In addition, the Atomic Beam was collimated by use of a two-dimensional optical molasses that was installed transverse to the Atomic–Beam direction. The flux of the Atomic Beam was 2×1010 atoms/s, an increase of a factor of 16 as a result of the collimation. The mean longitudinal velocity was ∼24.4 m/s, and the rms velocity spread of the slowed Atomic Beam was ∼1 m/s. Compared with other methods, we found that the Hoffnagle method is suitable for the generation of slow Atomic Beams to be used in an Atomic clock, which requires an ultralow magnetic field environment. This Atomic Beam was deflected by an angle of 30° by a one-dimensional optical molasses to separate it from laser light and high-velocity atoms.
Toward a cesium frequency standard based on a continuous slow Atomic Beam: preliminary resultsIEEE Transactions on Instrumentation and Measurement, 2001Co-Authors: Sang Eon Park, Taeg Yong Kwon, Sung Hoon YangAbstract:
A continuous Beam of slow cesium atoms was produced from a thermal Atomic Beam by laser cooling. This Beam was used as the source for the frequency standard. The Rabi-Ramsey spectrum was observed with the cold Atomic Beam. The Ramsey fringe of 62-Hz linewidth was obtained from a 21-cm-long microwave cavity. We found that the Rabi-Ramsey spectrum exhibited little dependence on the frequency of the pumping laser because of the long interaction time with the pumping light.
A continuous slow Atomic Beam for a cesium frequency standardConference on Precision Electromagnetic Measurements. Conference Digest. CPEM 2000 (Cat. No.00CH37031), 2000Co-Authors: Sang Eon Park, Sung Hoon YangAbstract:
A continuous slow cesium Atomic Beam was produced from a thermal Atomic Beam by using a laser-cooling technique. This Beam will be used as an Atomic source of a frequency standard. The mean longitudinal velocity and the rms velocity width of the slow atoms were approximately 24 m/s and 0.9 m/s, respectively.
K H Rieder – 3rd expert on this subject based on the ideXlab platform
Atomic Beam diffraction from solid surfacesReports on Progress in Physics, 1998Co-Authors: D Farias, K H RiederAbstract:
Atomic Beam techniques are presently being used in many branches of surface physics such as studies of the particle-surface physisorption potential, surface structure, surface phonons, nucleation and growth on metal and insulator surfaces, surface diffusion and accommodation and sticking of molecules. This review concentrates on diffractive phenomena from surfaces, which up to now were investigated mainly with helium. The theoretical background for diffraction calculations is outlined and representative examples of different applications are given. The main subjects covered are: structural determinations of chemisorbed and physisorbed systems, investigations of disordered surfaces, selective adsorption resonances, diffusion and nucleation studies and investigations of growth and phase transitions on surfaces. Diffraction results obtained with Ne, Ar, and are also summarized.