Investigation Of Diode-pumped All-solid-state Laser And Related Mode-locking Technology

Pulsed lasers have been used widely in various fields, such as opticalcommunication, medical, materials processing and nonlinear optics.Diode-pumped solid-state lasers have various advantages such as highconversion efficiency, long lifetime, compactness and high stability.Consequently, developing techniques for Q-switching or mode-locking indiode-pumped lasers has been burgeoning as a new exploration to get compactpulsed lasers. In this dissertation, we discussed the technologies of continuousoperation of fundamental and second harmonic generation, as well asQ-switching and mode-locking laser properties in diode-pumpedNd:Gd_0.42Y_0.58VO₄ solid-state lasers. The contents can be outlined as below:1. Review of the history and development of all solid state lasers. The mainapproaches and new results of all-solid-state pulses laser at present aresummarized. The optical properties of new Nd-doped mixed vanadatecrystal Nd:Gd_0.42Y_0.58VO₄ are Introduced.2. Investigation of the lasing properties of Nd:Gd_0.42Y_0.58VO₄ in experiments.The expression for diode-pumped solid-state laser properties is reached.The thermal effect of Nd:Gd_0.42Y_0.58VO₄ with different parameters for cavitylength and transmission rate are explored.3. Cr⁴⁺:YAG passively Q-switching and mode-locking laser of a new mixedvanadate crystal Nd:Gd_0.42Y_0.58VO₄ are explored. Cr⁴⁺:YAG possesses theproperties of ground-state saturable absorption (GSA) and exited-statesaturable absorption (ESA). And the relaxation times of GSA and ESA are inthe region of microsecond and picosecond, respectively. Thosecharacteristics can be applied to construct Q-switching and mode-lockinglasers. In our experiments, 2.7W Q-switching and mode-locking laser outputin the 1064nm is obtained.4. The theory of second harmonic generation simply introduced. The laseroutput of continuous waves ,Q-switching and mode-locking at 532nm ofNd:Gd_0.42Y_0.58VO₄ are obtained.5. 837mW Q-switching and mode-locking laser output at 1064nm of Nd:YVO₄is obtained with LT-GaAs as saturable absorber in our experiment, as wellas 1.35W Q-switching and mode-locking laser output at 1064nm ofNd:Gd0.42Y0.58VO4.