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arXiv · 1706.09028

Effect of saturable nonlinearity on cw stability in passively mode-locked lasers with fast saturable absorbers

Alain M. Dikande·P. Achankeng Leke
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Abstract

The self-starting dynamics of a model for passively mode-locked lasers with saturable absorber, in which the optical amplifier has a saturable nonlinearity, is examined. The basic assumption is that the laser will operate in the mode-locked regime when the continuous-wave regime becomes unstable. Within the framework of the modulational-instability analysis, a global map for the laser self-starting criteria is constructed. According to this map, the saturable nonlinearity enhances the input-field intensity required for laser self-starting. Analytical expression of the zero modulation-frequency regime of this threshold input field is derived, which turns out to be valid in the normal as well as in the anomalous dispersion regime, where evidence of self-starting is also given.

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Alain M. Dikande, P. Achankeng Leke. 2017-06-27. Effect of saturable nonlinearity on cw stability in passively mode-locked lasers with fast saturable absorbers. https://doi.org/10.1007/s00340-020-07510-8

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