Chaos studies on the super-ACO free electron laser

A laser with parameters modulated at a frequency f may respond not only at f and its harmonics, but also at is sub-harmonic frequencies f/n. The laser behaviour can become irregular though remaining deterministic. A gain modulation has been applied on the Super-ACO Free Electron Laser close to its natural frequency, via a change of the synchronization between the electron bunch and the optical pulse (detuning). Different macrotemporal structures can be observed such as 1T regime in which the laser is pulsed at the modulation period, 2T, chaos and so on. Such transitions can also be measured on the Free Electron Laser pulse temporal position. Bifurcation diagrams and attractors have also been recorded. Comparisons with simulations will be also given.