Open AccessTheoretical and experimental researches on Tm and Ho codoped Q-switching laser
Author(s) -
Lingling Qiao,
Fugui Yang,
Yonghua Wu,
Yougang Ke,
Xia Zhong-Chao
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.214205
Subject(s) - laser , duty cycle , population inversion , q switching , materials science , optics , rate equation , slope efficiency , resonator , pulse (music) , optical cavity , energy (signal processing) , pulse duration , atomic physics , physics , fiber laser , voltage , quantum mechanics , detector , kinetics
The distribution of population inversion has been obtained by solving the rate equations of a Tm and Ho codoped laser system. A giant pulse laser output of 88.4 mJ with pulse duration of 426 ns has been predicted at 0.1% duty cycle of LD pump source. In a 2 m ring resonator, the Tm, Ho:LuLF laser material has been side-pumped from three directions and Q-switched for acoustic-optic device. The slope efficiency is 6.36% in free running mode and 2.9% in Q-switching mode. When 3.25 J pump energy in 1 Hz repetition frequency is injected, it has been demonstrated that the laser pulse energy of 103.2 mJ with an optical-to-optical efficiency of 3.17% in the free running mode and 30.3 mJ with 0.93% optical-to-optical efficiency. When 3.5 J pump energy is injected, it has been obtained that the pulse energies of 129.3 mJ and 35.9 mJ in the two modes with optical-to-optical efficiencies of 3.69% and 1.02% respectively. The greatest dynamic to static ratio is 32.8%. The pulse duration is 417.2 ns when 3.25J pump energy is injected. If the ring resonator operates unidirectionally, the laser energy and the corresponding optical efficiency will be doubled, the result being in agreement with the theoretical analysis of rate equations.