一种新型的中性原子交流电磁囚禁

A Novel Ac Electro-magnetic Trap for Neutral Atoms

提出了一种新型的冷原子强场seeking态磁势阱 ,利用的是原子在交变四极场中受到的梯度力。计算结果表明通过选择合适的参数 ,可以控制势阱在轴向和径向的势阱深度。在得到一个径向势阱深度达 0 6mK ,纵向深度为 0 5mK的交流磁势阱 ,可以将温度为～ 10 0 μK的冷原子囚禁在径向 1mm ,纵向 4mm的范围内。如果撤消轴向囚禁 ,还可以获得一个径向囚禁深度为 1 8mK ,能将温度为～ 10 0 μK的冷原子囚禁在径向 5 0 μm范围内的新型磁导管。

A novel AC electro-magnetic trap for neutral atoms is proposed, which is based on the interaction of a magnetic dipole moment of trapped atoms with both an AC quadruple magnetic field in the transverse direction and a DC-bias magnetic field along the axial direction. The result shows that this is an ideal strong field-seeking trap for cold atoms. An atom guide with radial trapping potential over 1.2 mK is obtained and the guided atoms can be confined in a small region of r-50 μm. With changing the distribution of the bias magnetic field, an AC magnetic trap of cold atoms with axial potential depth 0.5 mK and radial potential 0.6 mK can be got, which is high enough to trap nearly all atoms with a temperature of -120μK.