  To understand the time-dependent quantum correlation in expanding universes,
we study the time-dependent entanglement entropy in the braneworld model. If we
take into account a generalized string cloud geometry caused by uniformly
distributed open strings, cosmologies on the braneworld result in the standard
Friedmann-Lema\^{i}tre-Robertson-Walker cosmologies with various matter
contents. On the dual field theory side, open strings are reinterpreted as a
fundamental matter, while the black hole mass corresponds to the excitation
energy of massless gauge bosons. In this work, we show how the string cloud
geometry is matched to various braneworld cosmologie,s for example, eternal
inflation, radiation-, and matter-dominated universes. Then, we investigate how
the entanglement entropy evolves in those expanding universes.
