Higgins Michael D, Greene Chris H
Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907.
Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, IN 47907.
Proc Natl Acad Sci U S A. 2025 May 6;122(18):e2503390122. doi: 10.1073/pnas.2503390122. Epub 2025 Apr 25.
This work treats resonant collisions between five identical ultracold bosons in the framework of the adiabatic hyperspherical representation. The five-body recombination rate coefficient is quantified using a semiclassical description in conjunction with an analysis of the lowest five-body hyperspherical adiabatic potential curves in a scattering length regime with no universal weakly bound tetramers, trimers, or dimers. A comparison is made between these results and the only existing experimental measurement of five-body loss in an ultracold gas of bosonic cesium atoms and with the lone theoretical estimation of the loss rate. The recombination rate for the process + + + + → + is also computed in a different regime of scattering lengths where there is one universal bound tetramer by implementing a few-channel quantum scattering calculation based on five-body hyperspherical potential curves and nonadiabatic couplings. Our calculations predict regions where five-body recombination can cause decay of the atom cloud in an ultracold gas that is even faster than 3-body and 4-body recombination, which can ideally be tested by using the current generation of box traps having nearly uniform density.
这项工作在绝热超球表示框架内研究了五个相同超冷玻色子之间的共振碰撞。在不存在通用弱束缚四聚体、三聚体或二聚体的散射长度范围内，结合对最低五条体超球绝热势曲线的分析，使用半经典描述对五体重组速率系数进行了量化。将这些结果与超冷铯原子气体中五体损失的唯一现有实验测量结果以及损失率的唯一理论估计值进行了比较。通过基于五体超球势曲线和非绝热耦合进行几通道量子散射计算，还在存在一个通用束缚四聚体的不同散射长度范围内计算了过程 + + + + → + 的重组率。我们的计算预测了在超冷气体中五体重组会导致原子云衰变的区域，其速度甚至比三体和四体重组还要快，这理想情况下可以通过使用当前密度几乎均匀的箱式阱来进行测试。
