A thermo-optical model describing the cavity stability and TEM<sub>00</sub>-mode volume of a repetitively pumped solid-state laser is developed and verified experimentally. The model predicts a maximum theoretical TEM<sub>00</sub> Gaussian-mode radius in the laser rod. This maximum mode radius is caused by a bifocusing of the cavity mode and is present even in gain-polarized materials that nominally suppress the effect of birefringence on beam polarization. The mode limitation effect is not eliminated by conventional optics and is reduced only marginally by the often-described technique of placing a second identical laser head in the cavity. A maximum mode radius implies a fundamental limit on the TEM<sub>00</sub>-mode energy that can be extracted from a given laser cavity.
© 2002 Optical Society of America
(140.3410) Lasers and laser optics : Laser resonators
(140.3560) Lasers and laser optics : Lasers, ring
(140.3570) Lasers and laser optics : Lasers, single-mode
(140.6810) Lasers and laser optics : Thermal effects
Matthew P. Murdough, Brian M. Flusche, Randall J. Knize, and Boris V. Zhdanov, "Thermo-Optical Model of Repetitively Pumped Solid-State Lasers," Appl. Opt. 41, 6385-6393 (2002)