论文标题
观察原子 - 离子结合状态的陷阱辅助形成
Observation of trap-assisted formation of atom-ion bound states
论文作者
论文摘要
成对的自由颗粒由于动量和能量守恒而无法在弹性碰撞中形成结合状态。然而，在许多超低实验中，颗粒在存在外部捕获电势的情况下发生碰撞，该诱捕势可以将质量中心和相对运动融入并有助于结合态的形成。在这里，我们报告了观察到一个超低$^{87} $ rb原子和一个线性保罗陷阱的单个被困的$^{88} $^{88} $^{88} $^{88} $^{88} $^{88}之间形成的分子状态的观察。我们表明，约束状态可以在二进制碰撞中有效形成，并提高非弹性过程的速率。 By observing electronic spin-exchange rate, we study the dependence of these bound states on the collision energy and magnetic field and extract the average molecular binding energy $E_{\textrm{bind}}=0.7(1)$ mK$\cdot k_B$ and the mean lifetime of the molecule $τ=0.5(1)\,μ$s, with good agreement with molecular-dynamics simulations.我们的模拟预测，分子寿命的高度不寻常的幂律分布，其平均值由极端，长寿事件主导。分子特性对捕获参数的依赖性为研究和控制超低碰撞提供了新的途径。
Pairs of free particles cannot form bound states in elastic collision due to momentum and energy conservation. In many ultracold experiments, however, the particles collide in the presence of an external trapping potential which can couple the center-of-mass and relative motions and assist the formation of bound-states. Here, we report on observation of weakly bound molecular states formed between one ultracold $^{87}$Rb atom and a single trapped $^{88}$Sr$^+$ ion in the presence of a linear Paul trap. We show that bound states can form efficiently in binary collisions, and enhance the rate of inelastic processes. By observing electronic spin-exchange rate, we study the dependence of these bound states on the collision energy and magnetic field and extract the average molecular binding energy $E_{\textrm{bind}}=0.7(1)$ mK$\cdot k_B$ and the mean lifetime of the molecule $τ=0.5(1)\,μ$s, with good agreement with molecular-dynamics simulations. Our simulations predict a highly unusual power-law distribution of molecular lifetimes with a mean that is dominated by extreme, long-lived, events. The dependence of the molecular properties on the trapping parameters opens new avenues to study and control ultracold collisions.
