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arXiv · 2108.09254

2D optical rogue waves affected by transverse carrier diffusion in broad-area semiconductor lasers with a saturable absorber

Kamel Talouneh·Reza Kheradmand·Giovanna Tissoni·Mansour Eslami
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Abstract

Statistics and dynamics of 2D rogue waves in a broad-area semiconductor laser with an intracavity saturable absorber are numerically investigated under the effect of transverse carrier diffusion. We show that lateral diffusion of carriers alters the statistics of rogue waves by enhancing their formation in smaller ratios of carrier lifetimes in the active and passive materials while suppressing them when the ratio is larger. Temporal dynamics of the emitted rogue waves is also studied and shown that finite nonzero transverse carrier diffusion coefficient gives them a longer duration. To further approach the realistic experimental situation, we also investigated statistics and dynamics of rogue waves by simulating a circular disk-shape pump which replaces the flat pump profile typically used in numerical simulations of broad-area lasers. We show that finite pump shape reduces the number emitted rogue waves per unit area for large carrier lifetime ratios and increases that for smaller values of the ratio in both below and above laser threshold. Temporal width of the emitted rogue waves is also shown to reduce as a consequence of removing the nonphysical effects of infinite flat pump on carrier dynamics.

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Kamel Talouneh, Reza Kheradmand, Giovanna Tissoni, Mansour Eslami. 2021-08-20. 2D optical rogue waves affected by transverse carrier diffusion in broad-area semiconductor lasers with a saturable absorber. https://arxiv.org/abs/2108.09254

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