We analyze the mode properties of a laser with a Gaussian gain profile by using the beam propagation method. The resonance properties of the Petermann K factor and the M2 beam quality are shown to be related in the vicinity of degenerate cavity geometries. K is unity for a confocal cavity, even under conditions with strong gain guiding, while M2 is a maximum.
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics