Dehmelt H, Yu N
Department of Physics, Box 351560, University of Washington, Seattle, WA 98195-1560, USA.
Proc Natl Acad Sci U S A. 1997 Sep 16;94(19):10031-3. doi: 10.1073/pnas.94.19.10031.
A modification of the Paul-Straubel trap previously described by us may profitably be operated in a Paul-Straubel-Kingdon (PSK) mode during the initial loading of an individual ion into the trap. Thereby the coating of the trap ring electrode by the atomic beam directed upon it in earlier experiments is eliminated, as is the ionization of an already trapped ion. Coating created serious problems as it spot-wise changed the work function of the ring electrode, which caused large, uncontrolled dc fields in the trap center that prevented zero-point confinement. Operating the Paul-Straubel trap with a small negative bias on the ring electrode wire is all that is required to realize the PSK mode. In this mode the tiny ring trap in the center of the long, straight wire section is surrounded by a second trapping well shaped like a long, thin-walled cylindrical shell and extending to the end-caps. There, ions may be conveniently created in this well without danger of coating the ring with barium. In addition, the long second well is useful as a multi-ion reservoir.
我们之前描述的保罗 - 施特劳贝尔阱的一种改进形式，在将单个离子初次加载到阱中的过程中，以保罗 - 施特劳贝尔 - 金登（PSK）模式运行可能会很有成效。由此，消除了早期实验中原子束照射在阱环电极上所导致的电极涂层，以及已捕获离子的电离现象。涂层引发了严重问题，因为它会逐点改变环电极的功函数，这在阱中心产生了大的、无法控制的直流电场，从而妨碍了零点约束。要实现PSK模式，只需在环电极丝上施加一个小的负偏压来操作保罗 - 施特劳贝尔阱即可。在这种模式下，长直导线段中心的微小环形阱被第二个捕获阱包围，该捕获阱形状如同一个长的薄壁圆柱壳并延伸至端盖。在那里，可以方便地在这个阱中产生离子，而不会有钡覆盖环的风险。此外，长的第二个阱可用作多离子储存器。
