International Journal of

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CSs have been theoretically predicted and recently experimentally demonstrated in broad area, vertical cavity driven semiconductor lasers (VCSELs) slightly below the lasing threshold. Above threshold, the simple adiabatic elimination of the polarization variable is not correct, leading to oscillatory instabilities with a spuriously high critical wave-number. To achieve real insight on the complete dynamical problem, we study here the complete system of equations and find regimes where a Hopf instability, typical of lasers above threshold, affects the lower intensity branch of the homogeneous steady state, while the higher intensity branch is unstable due to a Turing instability. Numerical results obtained by direct integration of the dynamical equations show that writable/erasable CSs are possible in this regime, sitting on unstable background

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A modulated holding beam shining a VCSEL above threshold can improve modulation bandwidth by adjusting the semiconductor laser’s relaxation oscillation frequency. The improved modulation characteristics are accompanied by reduced damping rate. By choosing correct parameters, dynamical behavior of system and cavity solitons is changed.

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Cavity Solitons (CSs) in an injected broad-area semiconductor laser with intracavity saturable absorber exhibit phase noise free and high-contrast intensity oscillations in period-one dynamical state. The continuous-wave periodic intensity oscillation of the CSs has a frequency well beyond the relaxation oscillation frequency and can be regarded as a photonic microwave source. Here we numerically investigate the effect of linewidth enhancement factor on the dynamical characteristics of CSs in the period-one regime. We show that in a fixed injection amplitude, it has a key role in shifting the oscillation frequencies of the period-one CSs and that its effects strongly depend on the cavity detuning value.