We demonstrate high-performance unidirectional and single-frequency ring-laser operation based on a diode-side-pumped Nd:YVO<sub>4</sub> bounce amplifier, obtained in a ring system both with and without a Faraday rotating element. Ring-laser operation with intracavity Faraday unidirectional element produces 15-W cw output in a TEM<sub>00</sub> and single-longitudinal mode with beam propagation parameter <i>M</i><sup>2</sup> < 1.1 with 35-W diode pumping. A novel non-Faraday-based ring laser uses a polarization-dependent output coupler and asymmetric polarization state in the birefringent Nd:YVO<sub>4</sub> gain medium and is demonstrated to produce highly unidirectional (1200:1) single-frequency output of 14 W in a TEM<sub>00</sub> mode with beam propagation factor <i>M</i><sup>2</sup> < 1.2 at 30 W of diode pumping.
© 2004 Optical Society of America
(140.3480) Lasers and laser optics : Lasers, diode-pumped
(140.3530) Lasers and laser optics : Lasers, neodymium
(140.3560) Lasers and laser optics : Lasers, ring
(140.3570) Lasers and laser optics : Lasers, single-mode
(140.3580) Lasers and laser optics : Lasers, solid-state
Benjamin A. Thompson, Ara Minassian, and Michael J. Damzen, "Unidirectional Single-Frequency Operation of a Nd:YVO4 Ring Laser With and Without a Faraday Element," Appl. Opt. 43, 3174-3177 (2004)