Numerical Simulation Of A Combined Grating DFB Surface-emitting Semiconductor Laser

Surface-emitting lasers are widely used in many areas nowadays, especially in thosefields that require low cost. Surface-emitting lasers are preferred over edge-emitting lasersin this kind of applications mostly because passivation of emitting area for reliableoperation is not needed, scalability at the wafer level is possible, testing and packaging aresignificantly simplified and thus reduces the cost.Currently, the only commercially available surface-emitting laser is VCSEL(vertical-cavity surface-emitting laser). Although VCSEL is already used massively infields like data communication, it bears a fundamental shortage of short cavity whichlimits its single-element output power. Horizontal-cavity surface-emitting lasersincorporating second-order DFB (distributed-feedback Bragg) grating however have allthe advantages mentioned above for surface-emitting lasers, meanwhile can overcome theshort cavity problem of VCSEL, which draws it a lot of research attention.In this thesis we first perform a brief introduction of surface-emitting DFB laser andits numerical analysis method. Then the author simulates a combined1stand2ndorderDFB surface-emitting laser with the self-programmed time-domain traveling-wavemethod based numerical solver. In the studied structure, the middle part of the1storderDFB grating in conventional DFB lasers is replaced by a section of2ndorder DFB gratingwhich works as the output coupler.The main content of this thesis are as follows:(1) A brief introduction of the structure and working principle of the studiedcombined grating DFB surface-emitting laser.(2) An introduction of the theory and implement of time-domain traveling-wavemethod based semiconductor laser solver, including optical governing equation, carrierrate equation, optical gain equation, pseudo random number generator and fast fouriertransformation. Then validate the solver by comparing the simulation results of apublished journal paper.(3) Simulation of the introduced laser structure with the self-programmed laser solverand the analysis and conclusion of the results. Then a group of optimized structure parameters are given with a single lope far field distribution and SMSR (side modesuppression ratio)>30dB.