Phase and intensity dynamics of a two-frequency laser submitted to resonant frequency-shifted feedback

Abstract

We propose an experimental and theoretical study of the dynamical regimes observed when the two modes of a two-frequency solid-state laser are coupled by frequency-shifted optical feedback. The detuning associated to the feedback is close to the frequency of the laser relaxation oscillations. Special attention is devoted to the dynamics of the phase of the beat note between the modes relative to the phase of an external radio-frequency reference. In particular, we analyze in detail the transition from phase locking to the external reference to phase drift. This transition occurs through a window of frequency locking without phase locking [Thévenin, Romanelli, Vallet, Brunel, and Erneux, Phys. Rev. Lett. 107, 104101 (2011)]. Furthermore, a large variety of dynamical behaviors, such as weak intensity modulation, self-pulsing, and chaos, are experimentally found. These results are successfully reproduced by a theoretical model based on coupled rate equations. The extension of the model to the description of other active media such as semiconductor lasers is briefly outlined.

Frequency-locked chaotic opto-RF oscillator

“…Control parameters are ∆ and Γ while the others are fixed to β = 0.6, η = 1.2 and ε = 0.097. These values have been previously measured [30] and allow good model-experiment agreement. A mapping of the behavior of this dynamical system has been computed, unraveling chaotic, periodic, phasebounded and phase-unbounded attractors, sometimes exhibiting multistability and fractal attraction basins.…”

Measuring the universal synchronization properties of driven oscillators across a Hopf instability

“…For more details on the model, and for the correspondence between the normalized and the physical quantities, see [22]. We have injected some noise in the system by replacing the pump parameter η with η(1 + 0.05ξ(s)), where ξ(s) is a δ-correlated, normally distributed stochastic process.…”

Excitable-like chaotic pulses in the bounded-phase regime of an opto-rf oscillator

“…The antiphase oscillation frequency allows retrieving the value of the coupling coefficient β [33]. The model equations, that wa have also used to analyze the synchronization dynamics of an optoradiofrequency (opto-rf) oscillator, based on the beating between the two polarization modes of a self-injected, dual-frequency laser [35], read as follows:…”