Abstract

The coupled rate equations with the spatial overlap effect for four-level passively Q-switched lasers are fully considered. A transcendental equation is derived for the residual fraction of the inversion density after the finish of the Q-switched pulse. Comprehensive calculations for the transcendental equation were executed to attain an analytical function for precisely fitting the residual fraction of the inversion density. With the fitting function, a pedagogical model with the correction for high output coupling is developed to straightforwardly analyze the output pulse energy and peak power. Detailed experiments are carried out to validate the model.

© 2021 Optical Society of America

Modelling end-pumped passively Q-switched Nd-doped crystal lasers: manifestation by a Nd:YVO₄/Cr⁴⁺:YAG system with a concave-convex resonator

P. H. Tuan, C. C. Chang, F. L. Chang, C. Y. Lee, C. L. Sung, C. Y. Cho, Y. F. Chen, and K. W. Su
Opt. Express 25(3) 1710-1722 (2017)

LED-side-pumped Nd:YAG laser with >20% optical efficiency and the demonstration of an efficient passively Q-switched LED-pumped solid-state laser

Chun Yu Cho, Chi Chih Pu, Kuan Wei Su, and Yung Fu Chen
Opt. Lett. 42(12) 2394-2397 (2017)

Timing jitter reduction of passively Q-switched solid-state lasers by coupling resonance between pumping and firing rates

Y. F. Chen, P. Y. Chien, C. C. Lee, K. F. Huang, and H. C. Liang
Opt. Lett. 45(10) 2902-2905 (2020)

High-peak-power electro-optically Q-switched laser with a gradient-doped Nd:YAG crystal

Meng-En Wei, Ting-Qing Cheng, Ren-Qin Dou, Qing-Li Zhang, and Hai-He Jiang
Opt. Lett. 46(19) 5016-5018 (2021)

All-solid-state passively Q-switched mode-locked Nd-doped fiber laser

L. A. Zenteno, H. Po, and N. M. Cho
Opt. Lett. 15(2) 115-117 (1990)