Diode Pumped Passively Q-switched And Mode Locked Laser At 1.3 ?m By V:YAG Saturable Absorber

With the high output energy and the peak power,the compact device structure and the long service life,the diode pumped laser at 1.3 ?m have been becoming more and more important to be studied.It draws lots of attentions because of its miniaturization,high efficiency,high reliability and the high beam quality.And it has a great influence on the scientific research,industrial production,medical and defense construction.The diode-pumped passively Q-switched and mode-locked laser at 1.3 ?m has been widely used in optical fiber communication,optical measurement,optical parametric oscillator,etc.So it has been concerned and attentioned by domestic laser research institute.But most of the literature research mainly concentrate in the long cavity resonator,and the laser repetition frequency is low.GHz-mode-locked laser in high-speed electro-optical sampling,communications and optical clock has been widely used,and high repetition frequency laser has become an important research content in the international.Therefore,based on the factors such as laser modes matching,crystal thermal lens effect,steady cavity condition,crystal characteristic and saturated absorber damage threshold,this paper optimizes the design of laser resonator.And finally 1.34 ?m Q-switched and mode locked laser with high repetition frequency and good indicators and the corresponding red laser have been achieved.The main contents are as follows:The development of the diode pumped laser and the 1.3?m Nd:YVO4 and Nd:GdVO4 laser,and its advantages and application fields have been introduced.The theory of the Q-switched and mode locked laser have been obtained.The parameters of the laser medi?m has been introduced in detail;and the introduction and analysis of the V:YAG saturable absorber have been introduced.By using the relevant theory to optimize the design of the laser cavity,with the Nd:YVO4 crystal and V:YAG as the saturated absorber,the 1.3 ?m Q-switched and mode locked laser with high repetition frequency is realized.Under the steady cavity condition,the repetition frequency,the average power and the Q-envelope pulse width at different power are compared,and the experimental results are analyzed.A diode-pumped passively Q-switched and mode-locked Nd:GdVO4 laser by V:YAG at 1.34 ?m with structure miniaturization and multi-GHz oscillations was realized.The experimental conditions about laser crystal were discussed combined with theoretical analysis.With the fluctuation mechanism theory,an analysis of the temporal shape of a single Q-switched envelope with mode-locked pulse trains has been presented.The mode-locked pulse repetition was up to 2 GHz.About 100%modulation depth of mode locking can be obtained.The Q-switched and mode-locked laser produced a maximum output power of 715 mW.Using a KTP crystal,the red laser of 671 nm red has also been obtained.