Fully vectorial simulation of Laser resonators including anisotropic media

Intra-cavity, anisotropic crystals can have substantial impact on the polarization-state and the transversal mode shape of laser resonators. In this presentation a flexible and fast simulation technique for the analysis of resonators containing homogeneous, anisotropic optical components is introduced. It is based on the generalization of the scalar Fox and Li algorithm for the transversal mode calculation to a fully vectorial model. Therefore we reformulate Fox and Li’s integral equation to a set of coupled operator equations which allow the flexible application of different light propagation techniques in different subdomains of the resonator. For resonator subdomains containing anisotropic media a fast Fourier Transformation (FFT) based angular spectrum of plane waves approach is introduced. This technique includes birefringence effects as well as intra-crystal diffraction and interface refraction at crystal surfaces. The resulting set of coupled operator equations is solved by the numerical efficient minimal polynomial extrapolation method. Numerical examples are presented which are in good agreement to experimental measurements.