Basic research for the realization of a coherent atomic beam using laser cooling methods

利用激光冷却方法实现相干原子束的基础研究

• 批准号: 10640392
• 负责人: NAKAGAWA Ken'ichi
• 金额: $ 2.18万
• 依托单位: The University of Electro-Communications
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640392/
• 关键词: Laser Cooling; BEC(Bose-Einstein Condensation); Atom Optics; Atom Laser; ボーズ・アインシュタイン凝縮

In this research project, we have developed basic techniques for the realization of coherent atomic beam sources, which can emit phase-coherent matter wave, using laser cooling methods. In order to realize such coherent atomic beam sources, we have developed an experimental apparatus for realizing Bose-Einstein condensation (BEC) of ^<87>Rb atoms using both laser cooling and evaporation cooling methods. As a result, we have developed a double-MOT(magnet-optical trap) system which could gather as much as 5×10^8 atoms in a glass cell at the extremely low pressure of the order of 10^<-11> torr. We have also developed a three-coil magnetic trap for the evaporation cooling. This trap can produce enough high magnetic field gradient (〜300 G/cm ) which is required for the tight confinement of atoms during the evaporation cooling. Using this magnetic trap, we could actually trapped and compressed the laser-cooled Rb atoms. Considering these preliminary experiments, we can expect the realization of BBC using the present apparatus if we will further optimize the apparatus and employ a rf-induced evaporation cooling method. We also consider the required experimental methods towards the practical coherent atomic beam sources for coherent atom optics and obtain future prospects for it.

在本研究计画中，我们发展了利用雷射冷却的方法来实现相干原子束源的基本技术，此原子束源可以发出相位相干的物质波。为了实现这种相干原子束源，我们研制了一套激光冷却和蒸发冷却相结合的实验装置，实现了^ Rb原子的玻色-爱因斯坦凝聚（BEC）<87>。因此，我们研制了一个双MOT（磁光阱）系统，它可以在10^Ω量级的极低压强下在玻璃池中收集多达5×10^8个原子<-11>。我们还开发了一种三线圈磁阱的蒸发冷却。该阱可以产生足够高的磁场梯度（~ 300 G/cm），这是在蒸发冷却期间紧密限制原子所需的。利用这个磁阱，我们实际上可以捕获和压缩激光冷却的Rb原子。考虑到这些初步的实验，我们可以期待实现BBC使用本设备，如果我们将进一步优化的设备，并采用射频诱导蒸发冷却方法。讨论了相干原子光学中实现实用化所需的实验方法，并对相干原子光学的发展前景进行了展望。

项目成果

Ken'ichi NAKAGAWA: "Coherent Atom Optics with Atom Lasers"The Review of Laser Engineering (in japanese). Vol.28. 160-165 (2000)

Kenichi NAKAGAWA：“原子激光器的相干原子光学”激光工程评论（日语）。

中川 賢一: "原子レーザーを用いたコヒーレント原子光学"レーザー研究. 28巻3号. (2000)

Kenichi Nakakawa：“使用原子激光器的相干原子光学”激光研究，第 28 卷，第 3 期（2000 年）。

中川 賢一: "原子レーザーを用いたコヒーレント原子光学"レーザー研究. 28. 160-165 (2000)

Kenichi Nakakawa：“使用原子激光器的相干原子光学”激光研究 28. 160-165 (2000)。