NONLINEAR DYNAMICS IN OPTICS: PRESENT AND NEW PERSPECTIVES
Nonlinear Dynamics in Optics:
Present and new Perspectives
Florence, Galileo Galilei Institute for Theoretical Physics
Wednesday, July 20
Abstracts of the contributions
Analogue spatiotemporal phenomena in long-delayed systems
When the delay is much longer than any other characteristic timescale, the data generated by a delayed system can be mapped into an equivalent spatiotemporal representation, in which the involved multiple timescales act as mutually independent spatial and temporal variables. This approach had considerable success, as the complex dynamics in the time-domain often results into simpler spatiotemporal patterns in the new representation. I discuss a general framework for the treatment of long-delayed systems in terms of partial differential equations in the thermodynamic limit, and present results from a series of experiments based on semiconductor lasers with long-delayed optoelectronic feedback. A variety of analogue spatiotemporal phenomena are shown to emerge depending on the local dynamics of the system, including domain coarsening and nucleation, front pinning and localized structures, critical phase-transitions and, more recently, excitable waves segments.
Time-crystal-oscillations in the output of a weakly modulated semiconductor laser with optical feedback near threshold
Time crystal oscillations in interacting, periodically-driven disordered
systems are highly regular oscillations that persist for long periods of
time, are robust to perturbations, and whose frequency differs from the
frequency of the driving signal [Yao and Nayak, 2018].
An elusive critical phenomenon: laser threshold as a function of system size
TO BE DEFINED.