Compact Non-Astigmatic Alexandrite Ring Laser with Unidirectional Single-Longitudinal-Mode operation

We report single-longitudinal-mode operation of a wavelength-tunable Alexandrite unidirectional ring laser with a simplified non-astigmatic design, producing continuous-wave output 0.69 W and in excellent TEM00 beam quality (M2 < 1.1) across its full pumping range.