K. Pyragas, WEAK AND STRONG SYNCHRONIZATION OF CHAOS, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 54(5), 1996, pp. 4508-4511
It is shown that synchronization in unidirectionally coupled chaotic s
ystems develops in two stages as the coupling strength is increased. T
he first stage is characterized by a weak synchronization, i.e., a res
ponse system subjected to a driving system undergoes a transition and
exhibits a behavior completely insensitive to initial conditions. Furt
her increase oi the coupling strength causes the dimension decrease of
the overall dynamics smd leads finally to a strong synchronization. I
n this stage, the dimension of the strange attractor in the full phase
space of the two systems saturates to the dimension of the driving at
tractor.