We present a method to control collisions between ultracold neutral atoms in the electronic ground state and trapped ions. During the collision, the neutral atom is resonantly excited by a laser to a low-field-seeking Rydberg state, which is repelled by the ion. As the atom is reflected from the ion, it is de-excited back into its electronic ground level. The efficiency of shielding is analyzed as a function of laser frequency and power, initial atom-ion collision energy, and collision angle. The suitability of several Rydberg levels of Na and Rb for shielding is discussed. Useful applications of shielding include the suppression of unwanted chemical reactions between atoms and ions, a prerequisite for controlled atom-ion interactions.

中文翻译：

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使用里德堡态的原子离子碰撞的光学控制

我们提出一种方法来控制电子基态中的超冷中性原子与被困离子之间的碰撞。在碰撞过程中，中性原子被激光共振激发到寻求低场的里德堡态，该态被离子排斥。当原子从离子反射时，它会被激发回其电子地平面。根据激光频率和功率，初始原子离子碰撞能量和碰撞角度来分析屏蔽效率。讨论了Na和Rb的几种Rydberg能级对屏蔽的适用性。屏蔽的有用应用包括抑制原子与离子之间有害的化学反应，这是受控的原子与离子相互作用的先决条件。