激光冷却铬原子的3维仿真分析

3-D analysis of laser-cooling Cr atoms

为了研究铬原子在激光冷却场中的3维表现形式,分析和探讨了铬原子与激光冷却场的相互作用过程,并基于半经典理论的多普勒力和偏振梯度冷却力的3维特性,采用4阶龙格-库塔算法模拟铬原子的3维运动轨迹,同时得到了铬原子的3维落点分布状态,当铬原子束经过激光冷却场后,其发散角变小,速率降低。结果表明,铬原子3维仿真结果与2维情况下的铬原子分布相吻合,并且能提供更全面和丰富的冷却信息。

In order to study the 3-D features of Cr atoms in laser cooling field, the interaction process of Cr atom and laser cooling field was analyzed. Based on the semi-classical theory of Doppler and polarization gradient force, the fourth-order Runge- Kutta algorithm was adopted to simulate 3-D trajectory of Cr atoms, at the same time, three-dimension distribution of them was also obtained. After passing through laser cooling field, the divergence angle of Cr atomic beam becomes smaller, and the corresponding velocity also decreases. The results show that the three-dimension features of Cr atoms agree with the twodimension cases, and can provide more comprehensive, richer cooling information.