论文标题
超低$^{39} $ k的三体重组的多通道性质
The multichannel nature of three-body recombination for ultracold $^{39}$K
论文作者
论文摘要
我们在动量空间中开发了一个完整的多通道自旋模型，以研究磁场上相同的碱金属原子的三体重组。该模型结合了精确的三原子自旋结构和逼真的成对原子 - 原子相互作用。通过忽略两个粒子之间的相互作用时，当射击粒子不处于其初始旋转状态时，我们得出了一个近似模型。通过这种近似模型，我们与最近在接近33.58 g [Chapurin $ et $ $ al $。，Phys Phys的钾39中对地面Efimov共振位置进行了极好的一致性。莱特牧师。 123，233402（2019）]。我们通过比较完整系统的数值结果来分析近似值的局限性，并发现它在同一自旋通道中较大磁场的Feshbach共振中分解。那里相关的三体闭合通道阈值更接近开放通道阈值，从而增强了相应的多通道耦合。因此，应包括那些Feshbach共振的相互作用的忽视组成部分。
We develop a full multichannel spin model in momentum space to investigate three-body recombination of identical alkali-metal atoms colliding in a magnetic field. The model combines the exact three-atom spin structure and realistic pairwise atom-atom interactions. By neglecting the interaction between two particles when the spectating particle is not in its initial spin state we arrive at an approximate model. With this approximate model we achieve excellent agreement with the recent precise measurement of the ground Efimov resonance position in potassium-39 close to 33.58 G [Chapurin $et$ $al$., Phys. Rev. Lett. 123, 233402 (2019)]. We analyze the limitations of our approximation by comparing to the numerical results for the full system and find that it breaks down for Feshbach resonances at larger magnetic fields in the same spin channel. There the relevant three-body closed channel thresholds are much closer to the open channel threshold, which enhances the corresponding multichannel couplings. Therefore the neglected components of the interaction should be included for those Feshbach resonances.
