Flashlamp-pumped, electro-optically Q-switched Cr,Tm,Ho:YAG oscillator delivering 505 mJ, 19 ns pulses with high stability

To the best of our knowledge, this corresponds to the highest peak power reported to date for flashlamp-pumped CTH:YAG oscillators, reaching 26.6 MW. The oscillator combines high pulse energy and short pulse duration with excellent energy stability, achieving a root-mean-square (RMS) energy fluctuation of 0.81% over a continuous 5-h test at 1 Hz.

We further investigate the influence of thermally induced lensing on the intracavity mode volume. By introducing a normalized mode-volume sensitivity parameter, we establish a clear correlation between the cavity design, thermal-lens dynamics and output stability. The results provide a practical guideline for optimizing high-energy CTH:YAG oscillators and for designing laser cavities that simultaneously offer high peak power and excellent pulse-to-pulse stability.