Theoretical study of short-pulse generation in DFB lasers by gain switching using a trapezoidal current
DOI:
https://doi.org/10.52673/18570461.26.2-81.04Keywords:
picosecond-duration pulses, DFB lasers, gain switching, trapezoidal current, Bragg modes, Fabry–Perotmodes, rate-equation-based modelAbstract
This paper analyzes the process of generating picosecond-order optical pulses using a distributed feedback (DFB) laser operating in the gain-switching regime under the influence of a trapezoidal-shaped current, employing a rate-equation-based model. The influence of the main parameters, such as the injected current value, the confinement factor, and the front-facet reflectivity, on the resulting characteristics of the optical pulses was investigated numerically. It was found that variations in these parameters lead to significant changes in pulse shape, peak power, and pulse duration. It was demonstrated that, for certain parameter values, nearly symmetric pulses can be obtained without a secondary trailing maximum. The parameter ranges for optimizing pulse characteristics were identified: peak power exceeding 15 W, pulse duration shorter than 20 ps, and the absence of a secondary trailing maximum. The obtained results may provide the basis for further experimental studies and may facilitate the use of such pulses in applications requiring short-duration, and high-power optical pulses.
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