title: Three-dimensional finite element computation of laser cavity eigenmodes [corrected].
abstract: A new method for computing eigenmodes of a laser resonator by the use of finite element analysis is presented. For this purpose, the scalar wave equation (delta + k2)E(x, y, z) = 0 is transformed into a solvable three-dimensional eigenvalue problem by the separation of the propagation factor exp(-ikz) from the phasor amplitude E(x, y, z) of the time-harmonic electrical field. For standing wave resonators, the beam inside the cavity is represented by a two-wave ansatz. For cavities with parabolic optical elements, the new approach has successfully been verified by the use of the Gaussian mode algorithm. For a diode-pumped solid-state laser with a thermally lensing crystal inside the cavity, the expected deviation between Gaussian approximation and numerical solution could be demonstrated clearly.
authors.affiliation: LAS-CAD GmbH, Brunhildenstrasse 9, 80639 München, Germany.
authors.forename: Konrad
authors.initials: K
authors.lastname: Altmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Pflaum
authors.forename: David
authors.initials: D
authors.lastname: Seider