  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.
