Greater than 100W diode-pumped Tm:YAG laser and its thermal issues

We discuss in this paper the serious thermal issues faced by a high average power (>100W) diode-side-pumped 2-micron Tm:YAG laser. An approach to quantify the thermal lensing with subsequent cavity designing to alleviate such thermal issues is presented. The simple approach outlined allows one to come up with appropriate cavity configurations quickly to overcome the thermal rollover and to power scale the laser. Such a technique is applicable to all high average power solid- state rod lasers which inevitably suffers from severe thermal aberrations.