Title :
115-W Tm:YAG diode-pumped solid-state laser
Author :
Honea, Eric C. ; Beach, Raymond J. ; Sutton, Steven B. ; Speth, Joel A. ; Mitchell, Scott C. ; Skidmore, Jay A. ; Emanuel, Mark A. ; Payne, Stephen A.
Author_Institution :
Lawrence Livermore Nat. Lab., CA, USA
fDate :
9/1/1997 12:00:00 AM
Abstract :
A compact diode-pumped Tm:YAG laser capable of generating greater than 100 W of CW power at 2 μm has been demonstrated. A scalable diode end-pumping architecture is used in which 805-nm radiation, coupled to the wing of the Tm3+3H6-3H 4 absorption feature, is delivered to the end of the laser rod via a lens duct. To facilitate thermal management, undoped YAG end caps are diffusion bonded to the central doped portion of the laser rod. For 2% and 4% Tm-doped rods of the same length, the lower doping level results in higher power, indicating that cross relaxation is still efficient while offering lower thermal stress and reduced absorption at the laser wavelength. Output powers for various output coupler reflectivities are compared to the predictions of a quasi-three-level model. Thermal lensing, cavity stability, and stress-induced birefringence measurements are described. The beam quality was analyzed with the 2% Tm-doped rod and a flat output coupler, yielding M2 values of 14-23
Keywords :
birefringence; laser cavity resonators; laser stability; laser transitions; laser variables measurement; optical pumping; solid lasers; 115 W; 2 mum; 805 nm; CW power; M2 values; Tm:YAG diode-pumped solid-state laser; Tm3+3H6-3H4 absorption feature; YAG:Tm; YAl5O12:Tm; beam quality; cavity stability; central doped portion; cross relaxation; diffusion bonded; flat output coupler; laser rod; lens duct; nm radiation; quasi-three-level model; scalable diode end-pumping architecture; stress-induced birefringence measurements; thermal management; thermal stress; undoped YAG end caps; Absorption; Diodes; Ducts; Lenses; Optical coupling; Power generation; Power lasers; Solid lasers; Thermal management; Thermal stresses;
Journal_Title :
Quantum Electronics, IEEE Journal of