Ahokas J, Semakin A, Järvinen J, Hanski O, Laptiyenko A, Dvornichenko V, Salonen K, Burkley Z, Crivelli P, Golovizin A, Nesvizhevsky V, Nez F, Yzombard P, Widmann E, Vasiliev S
Wihuri Physical Laboratory, Department of Physics and Astronomy, University of Turku, 20014 Turku, Finland.
ETH Zurich, Institute for Particle Physics and Astrophysics, 8093 Zurich, Switzerland.
Rev Sci Instrum. 2022 Feb 1;93(2):023201. doi: 10.1063/5.0070037.
We describe the design and performance of a large magnetic trap for storage and cooling of atomic hydrogen (H). The trap operates in the vacuum space of a dilution refrigerator at a temperature of 1.5 K. Aiming at a large volume of the trap, we implemented the octupole configuration of linear currents (Ioffe bars) for the radial confinement, combined with two axial pinch coils and a 3 T solenoid for the cryogenic H dissociator. The octupole magnet consists of eight race-track segments, which are compressed toward each other with magnetic forces. This provides a mechanically stable and robust construction with a possibility of replacement or repair of each segment. A maximum trap depth of 0.54 K (0.8 T) was reached, corresponding to an effective volume of 0.5 l for hydrogen gas at 50 mK. This is an order of magnitude larger than ever used for trapping atoms.
我们描述了一种用于存储和冷却氢原子（H）的大型磁阱的设计与性能。该磁阱在温度为1.5 K的稀释制冷机的真空空间中运行。为了实现大体积的磁阱，我们采用了线性电流（伊offe棒）的八极配置用于径向约束，并结合了两个轴向箍缩线圈和一个用于低温氢解离器的3 T螺线管。八极磁体由八个跑道形段组成，这些段通过磁力相互挤压。这提供了一种机械稳定且坚固的结构，每个段都有可能进行更换或维修。达到了0.54 K（0.8 T）的最大阱深，对应于50 mK时氢气的有效体积为0.5升。这比以往用于捕获原子的体积大一个数量级。
