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arXiv · 2205.08460

A stochastic nonlinear model of the dynamics of actively Q-switched lasers

Lukas Tarra·Andreas Deutschmann-Olek·Vinzenz Stummer·Tobias Flöry·Andrius Baltuska·Andreas Kugi
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Abstract

In this paper, we present a novel stochastic and spatially lumped multi-mode model to describe the nonlinear dynamics of actively Q-switched lasers and random perturbations due to amplified spontaneous emission. This model will serve as a basis for the design of (nonlinear) control and estimation strategies and thus a high value is set on its computational efficiency. Therefore, a common traveling-wave model is chosen as a starting point and a number of model-order reduction steps are performed. As a result, a set of nonlinear ordinary differential equations for the dynamic behavior of the laser during a switching cycle is obtained. A semi-analytic solution of these differential equations yields expressions for the population inversion after a switching cycle and for the output energy, which are then used to formulate a nonlinear discrete-time model for the pulse-to-pulse dynamics. Simulation studies including models with different levels of complexity and first experimental results demonstrate the feasibility of the proposed approach.

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Lukas Tarra, Andreas Deutschmann-Olek, Vinzenz Stummer, Tobias Flöry, Andrius Baltuska, Andreas Kugi. 2022-05-17. A stochastic nonlinear model of the dynamics of actively Q-switched lasers. https://doi.org/10.1364/oe.464508

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