Optically-pumped spin-exchange polarized electron source
Optically-pumped spin-exchange polarized electron source
复制标题
光泵浦自旋交换极化电子源
DOI：
--
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
M. Pirbhai
中科院分区：
文献类型：
--
作者：
M. Pirbhai
我们描述了一个原型极化电子源的操作。在缓冲气体的存在下，包含在单元中的铷蒸气被光学泵浦。来自钨丝的非极化电子被注入到电池中，并在与Rb原子进行自旋交换后被提取。我们比较了使用不同缓冲气体时源的性能。我们测量电子极化的减少，因为它们的注入能量的增加，但发现一个意想不到的制度，在较高的注入能量产生增加的电子极化伴随着40倍的电流增加，这表明在目标细胞中的慢二次电子的生产。在乙烯中，我们同时测量了4 μA的电子电流和24%的电子极化。这项工作提供了一个简单的，台式的，“交钥匙”的极化电子源的承诺。
We describe the operation of a prototype polarized-electron source. Rubidium vapor, contained in a cell, is optically pumped in the presence of a buffer gas. Unpolarized electrons from a tungsten filament are injected into the cell and extracted after undergoing spin exchange with the Rb atoms. We compare the performance of the source when different buffer gases are used. We measure a decrease in electron polarization as their injection energy increases, but find an unexpected regime at higher injection energies yielding increased electron polarization accompanied by a 40-fold increase in current, suggesting the production of slow secondary electrons in the target cell. With ethylene, we have measured electron currents of 4 μA simultaneously with electron polarizations of 24%. This work offers the promise of a simple, benchtop, “turnkey” source of polarized electrons.