Zero-lag long-range synchronization via dynamical relaying
  We show that simultaneous synchronization between two delay-coupled oscillators can be achieved by relaying the dynamics via a third mediating element, which surprisingly lags behind the synchronized outer elements. The zero-lag synchronization thus obtained is robust over a considerable parameter range. We substantiate our claims with experimental and numerical evidence of these synchronization solutions in a chain of three coupled semiconductor lasers with long inter-element coupling delays. The generality of the mechanism is validated in a neuronal model with the same coupling architecture. Thus, our results show that synchronized dynamical states can occur over long distances through relaying, without restriction by the amount of delay. 
Ingo Fischer, Raul Vicente, Javier M. Buldu, Michael Peil, Claudio R.   Mirasso, M. C. Torrent and Jordi Garcia-Ojalvo