Dellis Argyrios T, Shah Vishal, Donley Elizabeth A, Knappe Svenja, Kitching John
Opt Lett. 2016 Jun 15;41(12):2775-8. doi: 10.1364/OL.41.002775.
Laser spectroscopy of atoms confined in vapor cells can be strongly affected by the presence of background gases. A significant source of vacuum contamination is the permeation of gases such as helium (He) through the walls of the cell. Aluminosilicate glass (ASG) is a material with a helium permeation rate that is many orders of magnitude lower than borosilicate glass, which is commonly used for cell fabrication. We have identified a suitable source of ASG that is fabricated in wafer form and can be anodically bonded to silicon. We have fabricated chip-scale alkali vapor cells using this glass for the windows and we have measured the helium permeation rate using the pressure shift of the hyperfine clock transition. We demonstrate micro fabricated cells with He permeation rates at least three orders of magnitude lower than that of cells made with borosilicate glass at room temperature. Such cells may be useful in compact vapor-cell atomic clocks and as a micro fabricated platform suitable for the generation of cold atom samples.
囚禁在蒸汽池中的原子的激光光谱会受到背景气体存在的强烈影响。真空污染的一个重要来源是诸如氦气（He）之类的气体透过池壁的渗透。铝硅酸盐玻璃（ASG）是一种氦气渗透率比通常用于制造池体的硼硅酸盐玻璃低多个数量级的材料。我们已经确定了一种合适的以晶圆形式制造的ASG来源，它可以阳极键合到硅上。我们使用这种玻璃作为窗口制造了芯片级碱金属蒸汽池，并利用超精细时钟跃迁的压力位移测量了氦气渗透率。我们展示了在室温下氦气渗透率比用硼硅酸盐玻璃制成的池体至少低三个数量级的微制造池体。这种池体可能在紧凑型蒸汽池原子钟中有用，并且作为一个适合于产生冷原子样品的微制造平台。
