Atom trap and waveguide using a two-color evanescent light field around a subwavelength-diameter optical fiber
Atom trap and waveguide using a two-color evanescent light field around a subwavelength-diameter optical fiber
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DOI：
10.1103/physreva.70.063403
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发表时间：
2004-12-01
影响因子：
2.9
通讯作者：
Hakuta, K
中科院分区：
文献类型：
--
作者：
Le Kien, F;Balykin, VI;Hakuta, K
我们建议在亚波长直径的光纤中利用双色倏逝光场来捕获和引导原子。光纤携带红色失谐光和蓝色失谐光，两种模式都远离共振。当两个输入光场都是圆偏振的时，在横向平面中的总电势的一组捕获最小值形成为围绕光纤的环。这种设计允许将原子限制在光纤周围的圆柱壳中。当一个或两个输入光场为线偏振时，总势在横平面内有两个局部极小点。这种设计允许将原子限制在平行于光纤轴的两条直线上。由于光纤的厚度小，我们可以使用具有显著不同的倏逝衰减长度的远偏离共振场来产生具有大深度、大相干时间和大陷阱寿命的净电势。例如，一根半径为0.2 μ m的石英光纤传输30 mW的1.06 μ m波长的光和29 mW的700 nm波长的光，两个场在输入端都是圆偏振的，对铯原子来说，陷阱深度为2.9 mK，相干时间为32 ms，反冲加热限制的陷阱寿命为541 s。
We suggest using a two-color evanescent light field around a subwavelength-diameter fiber to trap and guide atoms. The optical fiber carries a red-detuned light and a blue-detuned light, with both modes far from resonance. When both input light fields are circularly polarized, a set of trapping minima of the total potential in the transverse plane is formed as a ring around the fiber. This design allows confinement of atoms to a cylindrical shell around the fiber. When one or both of the input light fields are linearly polarized, the total potential has two local minimum points in the transverse plane. This design allows confinement of atoms to two straight lines parallel to the fiber axis. Due to the small thickness of the fiber, we can use far-off-resonance fields with substantially differing evanescent decay lengths to produce a net potential with a large depth, a large coherence time, and a large trap lifetime. For example, a 0.2-mum-radius silica fiber carrying 30 mW of 1.06-mum-wavelength light and 29 mW of 700-nm-wavelength light, both fields circularly polarized at the input, gives for cesium atoms a trap depth of 2.9 mK, a coherence time of 32 ms, and a recoil-heating-limited trap lifetime of 541 s.