Computer simulation of transient processes in DFB semiconductor lasers

Abstract

Transient processes of semiconductor laser were simulated. These processes are best described by the variations of injected electron density and emitted photon density. Rate equations were chosen to describe the transient processes. Using the described model of transient processes, the unknown parameters of DFB (distributed feedback) semiconductor laser were defined from the experimental characteristics: the coefficient of optical amplification α, the factor of spontaneous emission β, the electron and photon lifetime, and the form of injection current pulse. The parameter estimation technique, which allows to define laser parameter values simply, quickly, and fairly precisely, was suggested.Transient processes were simulated for several DFB lasers and the coincidence of calculation results with experimental ones for all lasers was sufficient. The usable physical model was improved. Transient processes of lasers were simulated again and more precise results were obtained. The mismatch of analysed laser parameters with experimental ones did not exceed the limit of 10%.

Comment on “Room-Temperature Continuous-Wave Operation of Organometal Halide Perovskite Lasers”

“…, using a 3D photonic crystal. In contrast, a DFB laser only strongly modifies the photon mode density in a single direction and so has β ∼ 10 –4 . , In any case, as the other reported perovskite DFB lasers − have similar resonator principles and designs (and hence β) but do show a clear threshold, high β is not a reasonable explanation for the absence of a clear threshold in the light output. Given the existing literature, a clear threshold should be observable with pulsed excitation or a CW excitation at lower temperatures.…”

Investigation of High-Speed Transient Processes and Parameter Extraction of InGaAsP Laser Diodes

“…and simulated pulse characteristics P(simul.) of optical power (Vasiliauskas et al, 2007) Table 3. Fourth model: computer simulation results (2) (Vasiliauskas et al, 2007) www.intechopen.com…”

“…13. Simulated electron density (N) and experimental chirp (Δf) pulse characteristics (Vasiliauskas et al, 2007) a), and experimental P(exp.) and simulated pulse characteristics P(simul.)…”

“…14 and 15). Mp is for optical power characteristic (Vasiliauskas et al, 2007) Table 4. Mismatch (%) of simulation data to experimental results (Vasiliauskas et al, 2007) …”

“…The results obtained were also compared to those of other authors (Agrawal & Dutta, 1993). for different spontaneous emission factors β (Vasiliauskas et al, 2007) The output optical power of the semiconductor laser was calculated by using these equations (Agrawal & Dutta, 1993): …”