  In a world of hardening borders, nations may deprive themselves of enjoying
the benefits of cooperative immigrants. Here, we analyze the effect of
efficient cooperative immigrants on a population playing public goods games. We
considered a population structured on a square lattice with individuals playing
public goods games with their neighbors. The demographics are determined by
stochastic birth, death, and migration. The strategies spread through imitation
dynamics. Our model shows that cooperation among natives can emerge due to
social contagion of good role-model agents that can provide better quality
public goods. Only a small fraction of efficient cooperators, among immigrants,
is enough to trigger cooperation across the native population. We see that
native cooperation achieves its peak at moderate values of immigration rate.
Such efficient immigrant cooperators act as nucleation centers for the growth
of cooperative clusters, that eventually dominate defection.
