Evaluating the short-term unpredictability of semiconductor lasers subject to multiple time-delayed feedbacks.

Project Details


Lasers are complex dynamical devices. Though they typically behave in a stable manner, external
perturbations such as optical feedback can easily trigger various dynamical behaviors like oscillations and
even chaos. The latter proved to be interesting for applications in secure communications or cryptography,
however optimizing the chaotic behavior remains a challenge. A key feature is the time after which the
chaotic dynamics of the laser becomes unpredictable, the so-called short-term unpredictability. But we
face a fundamental difficulty: as of today, there is no accurate and easily measurable figure of merit
evaluating how fast the laser chaos becomes unpredictable.
This joint project therefore targets the identification of key features quantifying the short-term
unpredictability and the derivation of a meaningful figure of merit that could be easily estimated
experimentally and theoretically.
To do so, we will use a laser with two distinct time-delayed optical feedback loops as testbed. Extra
complexity of the laser system, such as adding an extra feedback loop, is often seen as a requirement to
improve the unpredictability of the laser chaos. Thus, we will be able to investigate this assumption in
detail. At the same time, our work will pave the way towards a better understanding of time-distributed
feedbacks on the laser dynamics which could benefit optical sensing applications and the development of
reliable multi-wavelength lasers relying on feedback for stabilization
Effective start/end date1/01/2231/12/23


  • chaos
  • Nonlinear dynamics
  • laser dynamics
  • optical feedback

Flemish discipline codes

  • Photonics, optoelectronics and optical communications
  • Lasers and quantum electronics
  • Nonlineair sciences
  • Semiconductor devices, nanoelectronics and technology