In the right conditions, removing one particle from a multipartite bound state can make it fall apart. This feature, known as the "Borromean property", has been recently demonstrated experimentally in Efimov states. One could expect that such peculiar behavior should be linked with the presence of strong inter-particle correlations. However, any exploration of this connection is hindered by the complexity of the physical systems exhibiting the Borromean property. To overcome this problem, we introduce a simple dynamical toy model based on a discrete-time quantum walk of many interacting particles. We show that the particles described by it need to exhibit the Greenberger-Horne-Zeillinger (GHZ) entanglement to form Borromean bound states. As this type of entanglement is very prone to particle losses, our work demonstrates an intuitive link between correlations and Borromean properties of the system. Moreover, we discuss our findings in the context of the formation of composite particles.

中文翻译：

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离散时间量子行走中的 Borromean 状态

在适当的条件下，从多粒子结合状态中去除一个粒子可以使其分崩离析。这个特性，被称为“Borromean 特性”，最近在 Efimov 州通过实验得到了证明。人们可以预期这种奇特的行为应该与强烈的粒子间相关性的存在有关。然而，对这种联系的任何探索都受到表现出 Borromean 属性的物理系统的复杂性的阻碍。为了克服这个问题，我们引入了一个简单的动态玩具模型，该模型基于许多相互作用粒子的离散时间量子行走。我们表明，它所描述的粒子需要表现出格林伯格-霍恩-蔡林格 (GHZ) 纠缠以形成 Borromean 束缚态。由于这种纠缠很容易造成颗粒损失，我们的工作证明了系统的相关性和 Borromean 属性之间的直观联系。此外，我们在复合颗粒形成的背景下讨论了我们的发现。