Three-dimensional finite element analysis of laser cavities

摘要

In a Finite Element Analysis (FEA) method to compute eigenmodes, time dependent dynamic mode structure, stability, beam quality, and laser power output of a laser cavity, the number of nodes of the discretization grid necessary to obtain sufficient accuracy is reduced by the use of a transformation of the differential equations describing the electromagnetic field. This removes the periodic fluctuations of the electromagnetic field from the mathematical expressions by the use of a product representation for the field variables with one term representing the periodic field oscillations, which have a scale length corresponding to the wave length, and another term representing the transformed field variables which are almost free of these small scale oscillations.