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A comprehensive numerical model for the analysis of vertical-surface emitting-lasers is presented. An optical, electrical, and thermal submodel are introduced. The complete analysis is based on the method of lines. The temperature distribution and the current density are calculated in the whole structure. The optical behavior is investigated with a full vectorial wave equation in cylindrical coordinates. Multimode effects are considered when calculating the optical output power. A rate equation for electrons and holes is used, which includes diffusion and recombination effects inside the quantum well. By combining all submodels a self consistent solution is found.

We compare the results of different optical vertical-cavity surface-emitting laser models on the position-dependent effects of thin oxide apertures. Both scalar and vectorial models as well as hybrid models are considered. Physical quantities that are compared are resonance wavelength, threshold material gain, and modal stability. For large device diameters and low-order modes, the agreement between the different models is quite good. Larger differences occur when considering smaller devices and higher order modes. It is also observed that the spread in the resonance wavelengths is smaller than that for the threshold material gain.

An algorithm is proposed for the computation of resonator wavelength of vertical cavity surface emitting lasers by Cauchy's formula and the method of lines. To calculate the laser modes an implicit eigenvalue problem has been solved. A pole-free complex function has been developed which allows the determination of all roots within the observed complex area. To test the proposed method several wavelengths of a 1.55 μm laser have been computed and compared with direct and iterative algorithms.

The analysis of polarization and propagation effects in optical fibers with elliptical deformed cross section is an important issue of fiber communication. Especially, the investigation of group velocity and group index in such deformed fibers are necessary. For that reason a method to solve the full vectorial wave equation in an elliptical coordinate system is presented. The analysis is done by the method of lines where the wave equation is derived from the generalized transmission line equations. The solutions are obtained by one dimensional discretization and by introducing Fourier expansions in the wave equation. Results are presented for dielectric elliptical waveguides with different eccentricities.