We numerically study the dynamics of vertical cavity surface-emitting lasers (VCSELs) based on the current-dependent gain model subjected to current modulation. For a few hundred MHz frequency of injection current, the threshold current is reduced and polarization switching is accompanied by an anti-phase dynamics of polarization modes. Pulse packages are found and compared with those found in the literature. The behaviour of pulse packages is studied in terms of the modulation parameters. For a few GHz frequency of injection current, the dynamics of VCSELs presents chaotic behaviour.

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Abstract. We use the generalized Lugiato-Lefever model to investigate the phenomenon of Kerr optical frequency comb generation when group-velocity dispersion is null. In that case, the first dispersion term that plays a leading role is third-order dispersion. We show that this term is sufficient to allow for the existence of both bright and dark solitons. We identify the areas in the parameter space where both kind of solitons can be excited inside the resonator. We also unveil a phenomenon of hysteretic switching between these two types of solitons when the power of the pump laser is cyclically varied.

In this paper, we apply the technique of back-action cooling to investigate the effects of both optical and mechanical nonlinearities in optomechanical cooling systems. It is shown that cooling of the nanomechanical oscillator to its ground state is limited by the effects of these nonlinearities. The qualitative result is justified quantitatively by comparing, for the same parameters, our analytical minimum phonon number with the experimental one.