<p> The semiconductor distributed feedback (DFB) laser is mainly characterised by the single-longitudinal-mode operation with a narrow spectral linewidth, which leads to its wide application in fiber-optic communication systems. Several numerical models ranging from physics-based to phenomenological ones have been developed with different level of complexities and for different applications. However, with the continuous improvement in designs of DFB lasers, more efficient simulation methods with sufficient accuracy are highly desirable. In this thesis, I mainly focus on developing new one-dimensional (ID) simulation methods of DFB lasers with improved computational efficiency and physical insight without compromise on accuracy. Further, a new design idea for DFB lasers are explored and investigated by using the simulation techniques developed.</p> <p> Starting with the well-known ID time-dependent coupled-wave equations, we have examined two different solution schemes, i.e. the traveling wave model (TWM) and the standing wave model (SWM). The TWM has the merits of straightforward implementation, and being able to simulate a large variety of the structure even if the laser cavity has a small quality factor (Q-factor). Firstly, the existing time-domain solution schemes are reviewed and compared under a unified framework. A high-order split-step traveling wave method is then developed. Its validity and efficiency are examined through the comparison made with the conventional split-step scheme.</p> <p> For laser structures with large variations of the carrier/photon density, however, the TWM is not computationally economical. The SWM on the other hand has its advantages in dealing with the laser cavity with a relatively large Q-factor. Two different standing wave models are proposed to simulate the index-coupled and gain-coupled DFB lasers, respectively. The complexities of these two numerical models are further reduced through an approximation made on the time-dependent carrier distribution. Finally, the proposed SWMs are reduced to a similar form to the rate equation formulations for establishing the linkage between the 1D model and the rate equation model. More physical insights into the conventional and powerful rate equations will be gained through this linkage.</p> <p> The final part of the thesis focus on the analysis of a novel design of single-mode operation DFB laser employing the dispersive grating. The design idea is verified by the proposed SWM.</p> / Thesis / Doctor of Philosophy (PhD)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/18793 |
| Date | 01 1900 |
| Creators | Xi, Yanping |
| Contributors | Huang, Wei-Ping, Electrical and Computer Engineering |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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