标题： 四玻色子束缚态来自功能重正化群 显示英文标题

标题： Four-boson bound states from a functional renormalisation group

摘要： 我们使用功能重正化群来研究接近单位极限的玻色系统中的三体和四体态的谱。 我们的有效作用量包括四原子部分的所有与能量无关的接触相互作用，并我们引入了一个运行的三体场来消除涉及原子-原子-二聚体通道的耦合。 结果表现出与精确方法相似的定性行为。 我们使用的截断作用量导致在这些处理中看到的两个四体态过度结合。 它还产生了一个第三态，尽管仅在非常狭窄的两体散射长度范围内。 显示英文摘要

摘要： We use the functional renormalisation group to study the spectrum of three- and four-body states in bosonic systems around the unitary limit. Our effective action includes all energy-independent contact interactions in the four-atom sector and we introduce a running trimer field to eliminate couplings that involve the atom-atom-dimer channel. The results show qualitatively similar behaviour to those from exact approaches. The truncated action we use leads to overbinding of the two four-body states seen in those treatments. It also generates a third state, although only for a very narrow range of two-body scattering lengths.