The work in this thesis is focused on the complex dynamics of semiconductor laser (SL) devices which receive time-delayed feedback from an external cavity or are delay-coupled with a second semiconductor laser. We investigate fundamental properties of the dynamics and study the utilization of transient complex dynamics of a single SL arising from delayed feedback and external signal injection for a neuro-inspired photonic data processing scheme. Based on experiments and numerical modelling, we investigate systems of two coupled SLs, gaining insights into the role of laser and coupling parameters for the synchronization characteristics of these systems. We link certain features of the synchronization dynamics, like intermittent desynchronization events, to the underlying nonlinear dynamics in the coupled laser system.
Our research thus combines both fundamental insights into delay-coupled lasers as well as novel application perspectives.