  We investigate multipartite entanglement of the quantum Ising model with
transverse fields for a slow quantum quench crossing a critical point. The
multipartite entanglement is quantified by quantum Fisher information with the
generator defined as the operator of the ferromagnetic order parameter due to
the system symmetry. The quench dynamics begin with the ground state of the
large transverse field in the paramagnetic phase, and then the transverse field
is driven slowly to cross a quantum critical point and ends with a zero
transverse field. Based on methods of matrix product state, we calculate the
quantum Fisher information density of the final state. Numerical results of
both linear and nonlinear quench show that the quantum Fisher information
density of the final state scales as a power law of the quench rate, which has
an opposite exponent of the Kibble-Zurek scaling. Our results reveal that the
multipartite entanglement provides a new viewpoint to understand the dynamics
of quantum phase transition. Based on the observation of entanglement in the
quenched state, we also expect that our result would inspire approaches for
preparing multipartite entangled states in quantum information processing.
