Beam Characteristics of Planar Waveguide Lasers with Hard-edge Unstable Resonators
硬边非稳腔平面波导激光器的光束特性

The method of numerical simulation based on coordinate transformation and diffraction theory was adopted to analyze the beam characteristics of waveguide lasers with hard-edge unstable resonators.Output beam quality was investigated considering non-uniform pumping and gain saturation.The beam characteristics with positive and negative branch unstable resonators were compared for end-and edge-pumped lasers.It is shown that near diffraction-limited beam qualities could be achieved with optimized off-axis hard-edge unstable resonators.For edge-pumped and end-pumped lasers were under the same pumping non-uniformity,M2 factors with positive branch unstable resonators are 3.9 and 2.3,while those with negative ones are 1.8 and 1.7,respectively.