雷射冷卻







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雷射冷卻是指運用一道或多道雷射將原子、分子冷卻的技術。1974年，斯坦福大学的T.W.汉森等人提出以激光将气体分子减速的设想[1]。




目录






  • 1 多普勒冷却


  • 2 诺贝尔奖


  • 3 相關條目


  • 4 參考資料





多普勒冷却


多普勒冷却是一种利用多普勒效应达到原子冷却的技术。当激光传播方向与原子运动方向相反时，原子感受到激光的频率比实际频率略高。使激光频率比原子的共振频率略低，原子迎着激光前进时仍然可以吸收光子而进入激发态。当原子从激发态回落至基态时，释放的光子能量比之前吸收的略大，导致原子损失能量。由于入射光子动量方向恒定，而放出的光子的动量角分布是均匀的，原子的动量亦得以改变。[2]



诺贝尔奖


1997年的诺贝尔物理学奖授予朱棣文、威廉·丹尼尔·菲利普斯、克洛德·科昂-唐努德日，以表彰他们在激光致冷领域的贡献。[3]



相關條目


  • 協同冷卻


參考資料





  1. ^ Hänsch, Theodor W., and Arthur L. Schawlow. "Cooling of gases by laser radiation." Optics Communications 13.1 (1975): 68-69.


  2. ^ Wineland, David J., Robert E. Drullinger, and Fred L. Walls. "Radiation-pressure cooling of bound resonant absorbers." Physical Review Letters 40.25 (1978): 1639.


  3. ^ The Nobel Prize in Physics 1997. [2016-12-05]. 

























































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