Characteristics Of All-solid Urltrashort Pulse Laser

Since the semiconductor saturable absorber mirror (SESAM) was firstly introduced by Ursula Keller in 1992, there was a new method and way of the studies on the all-solid ultrfast pulse lasers. The introduction of the SESAM has solved the problem of the all-solid pulse lasers lacking regular pulse trains. Since the introduction, the average powers, pulse durations, pulse energies and pulse repetition rates of the compact ultrafast solid-state lasers have improved greatly and promoted the development of the studies of the ultrafast lasers. Ultrafast lasers are the pulses with the picosecond or femtosecond pulse durations. The ultrafast lasers have the characteristics of high pulse energies, broad spectrum and short emission time of the lasers, and have wide applications in the physics, biology, laser spectroscopy, optical communications and nonlinear frequency conversion etc. As the superiorities of the SESAM on the self-startup, good stabilities and simple cavity structures, it becomes the study focus in recent years. This thesis presents results of theoretical and experimental researches on the performance of passively model-locked Nd:YVO₄ and Nd:GVO₄ solid-state lasers with SESAM. The contents can be outlined as follows:1. The characteristics of the SESAM mode-locking. Introduce the the characteristics of the SESAM mode-locking, and the advantages of the SESAM, contrasting with the other mode-locking technologies.The work mode and theories of the SESAM are also presented.2. Using Nd:YVO₄ crystal, high output power and short pulse laser is obtained. With the better design of the laser cavity, the continuous-wave mode-locked laser output with the SESAM is achieved. At the pump power of 10.07W, we achieve 3.508W mode-locked laser output, with the efficiency of 32.69%.3. Improve the laser cavity structure, and obtain single mode-locked laser output. The applications of the laser are great improved. At the pump power of 10.07W, 3.027W output power is obtained with the pulse duration 7.6ps. As its single output, it has higher efficiency of the pump power and higher application value.4. With KTP, 532nm green mode-locked laser with short pulse is obtained. The maximum output power is 400mW and the pulse duration is 5.5ps.Since the high reflection waste of the SESAM, 400mW green laser is obtained.