Loftus Thomas H, Ido Tetsuya, Ludlow Andrew D, Boyd Martin M, Ye Jun
JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309-0440, USA.
Phys Rev Lett. 2004 Aug 13;93(7):073003. doi: 10.1103/PhysRevLett.93.073003.
We present an extensive study of the unique thermal and mechanical dynamics for narrow-line cooling on the 1S0-3P1 88Sr transition. For negative detuning, trap dynamics reveal a transition from the semiclassical regime to the photon-recoil-dominated quantum regime, yielding an absolute minima in the equilibrium temperature below the single-photon-recoil limit. For positive detuning, the cloud divides into discrete momentum packets whose alignment mimics lattice points on a face-centered-cubic crystal. This novel behavior arises from velocity selection and "positive feedback" acceleration due to a finite number of photon recoils. Cooling is also achieved with blue-detuned light around a velocity where gravity balances the radiative force.
我们对88Sr在1S0-3P1跃迁上进行窄线冷却的独特热动力学和机械动力学展开了广泛研究。对于负失谐，阱动力学揭示了从半经典区域到光子反冲主导的量子区域的转变，在低于单光子反冲极限的平衡温度下产生了绝对最小值。对于正失谐，原子云分裂成离散的动量包，其排列类似于面心立方晶体上的晶格点。这种新颖的行为源于速度选择和由于有限数量的光子反冲导致的“正反馈”加速。在重力平衡辐射力的速度附近，利用蓝失谐光也能实现冷却。
