Passively Q-Switched Tm,Ho：YVO4 Laser with Cr：ZnS Saturable Absorber at 2 μm

A stable diode-pumped passively Q-switched Tm,Ho：YVO4 laser with Cr：ZnS saturable absorber is reported. The shortest pulse duration of -500 ns with the central wavelength of 2041 nm is obtained at the pump power of 7.4 W, corresponding to the pulse energy of 3.5 μd at repetition rate of 65 kHz.     

End-Pumped Tm:YAG Ceramic Slab Lasers

Lasers from a Tm：YAG slab is end-pumped by continuous-wave output of the Tm：YAG ceramic ceramic am~e reported for the t~rst time to our best knowledge. The Tm：YAG ceramic a laser diode with central wavelength 792nm. At room temperature, the maximum power is 4.5 W, and the sloping efficiency is obtained to be 20.5%. The laser spectrum is centered at 2015nm.     

Comparison of Nd:YAG Ceramic Laser Pumped at 885nm and 808nm

Laser performance of 1064 nm domestic Nd：YAG ceramic lasers for 885 nm direct pumping and 808 nm traditional pumping are compared. Higher slope efficiency of 34% and maximum output power of 16.5 W are obtained for the 885nm pump with a 6ram length 1 at.% Nd：YAG ceramic. The advantages for 885nm direct pumping are discussed in detail. This pumping scheme for highly doping a Nd：YAG ceramic laser is considered as an available way to generate high power and good beam quality simultaneously.     

Ce:YAG晶体和透明陶瓷的光学和闪烁性能

采用温梯法生长了Ce:YAG晶体和真空烧结法制备了Ce:YAG透明陶瓷,并对晶体和透明陶瓷的光学和闪烁性能进行了对比研究.Ce:YAG晶体和陶瓷都具有位于230,340和460 nm波段的Ce³⁺离子的特征吸收带和540 nm附近的发射峰,但Ce:YAG晶体同时存在296和370 nm的色心吸收,其发射峰位于398 nm,而透明陶瓷中不存在.Ce:YAG晶体和陶瓷的X射线荧光中均存在520 nm附近的Ce³⁺离子发射,但晶体中还存在由反格位缺陷引起的300 nm 关键词： Ce:YAG 闪烁晶体 透明陶瓷     

Synthesis and microstructure analysis of composite Nd:YAG/YAG transparent ceramics

Transparent Nd：YAG/YAG composite ceramics are synthesized by solid-state reaction method using high- purity Y203, A1203, and Nd203 powders as raw materials. The mixed powder compacts are sintered at 1780 ℃ for 10 h under vacuum and annealed at 1450 ~C for 20 h in air. The Nd：YAG/YAG ceramics exhibit a pore free structure with an average grain size of about 30 μm. The microstructure of the Nd：YAG/YAG composite transparent ceramics is studied and there is no interface between Nd：YAG and YAG ceramics. The Nd ion distribution in one grain is also studied, which shows that there is no segregation of Nd ions as in Nd：YAG crystals.     

Nd∶Y_3Al_5O_(12)透明激光陶瓷的光学性能

采用固相合成法制备了Nd:Y3Al5O12(Nd:YAG)透明激光陶瓷.用V型棱镜法测量了Nd:YAG陶瓷的折射率.用干涉仪测量了陶瓷的光学均匀性.测试了Nd:YAG透明陶瓷的透过光谱、吸收光谱和荧光光谱,在1064 nm的直线透过率达到80%以上,并计算其吸收系数、吸收截面和发射截面.根据Judd-Ofelt理论,拟合出晶体场强度参数Ωt(t=2, 4, 6)为:Ω2=0.32×10-20 cm2, Ω4=2.72×10-20 cm2, Ω6=5.39×10-20 cm2.荧光辐射寿命τrad为248.61 μs,计算的荧光分支比β为:β1=34.613%, β2=52.814%, β3=10.697%, β4=0.621%.并将Nd:YAG陶瓷的吸收光谱、荧光光谱与Nd:YAG单晶进行了对比.     

Investigation on the scattering effect of ceramic Nd:YAG

This paper investigates the scattering effect of domestic 0.5 at{\%} ceramic Nd:YAG. An effective method has been utilized to measure the scattering and absorption coefficients. An end-pumped continuous wave (CW) Nd:YAG ceramic laser was also demonstrated. A maximum output power of 6.7~W at 1064~nm was obtained at an 808-nm pump power of 32.9~W. Conversion efficiency and slope efficiency have been achieved. This indicates that scattering has an important effect on the optical performance of ceramic Nd:YAG.     

Comparative spectroscopic investigation of Yb-doped YAG, YSAG and YLaO3 transparent ceramics

Transparent Yb doped YAG, YSAG and YaLaO3 ceramics are fabricated by using the co-precipitation method. The spectral properties and thermal parameters of these Yb doped cubic phase transparent ceramics are compared, and their different and potential applications are also analysed. The absorption cross-section and the emission cross-section of these ceramics are measured and calculated. The essential properties of these materials especially for the rep-rated pulsed high-energy diode-pumped solid-state lasers are investigated. The results show that Yb doped YAG, YSAG and YaLaO3 are all suitable materials used for diode-pumped solid-state lasers.     

Yb3+,Er3+:YAG透明陶瓷的制备和1.5 μm波段光谱性能研究

采用固相法和真空烧结技术制备了5at%Yb³⁺,2at％Er³⁺:YAG透明陶瓷.在1760 ℃真空烧结30 h后, 陶瓷样品具有较高透过率.SEM观察表明制备的透明陶瓷在晶粒和晶界处无气孔、第二相的存在.样品的吸收光谱和荧光光谱的测试结果表明: Yb³⁺在940nm波长处有具有较强的吸收系数.样品在1030nm波长的荧光寿命仅为0.274 ms,以及在1.5μm波段的荧光衰减寿命曲线中,初始的荧光强度呈上升趋势,这些表明了Yb,Er:YA 关键词： Er Yb:YAG透明陶瓷 1.5 μm荧光光谱 Judd-Ofelt理论     

Efficient Tm：YAG Ceramic Laser at 2 μm

We demonstrate a high-efficiency continuous-wave Tm： YAG ceramic laser pumped with a Ti：sapphire laser. An output power up to 860mW is obtained under an absorbed pump power of 2.21 W at 785nm, corresponding to a slope efficiency of 42.1% and optical to optical efficiency of 22%. The measured central wavelength is 2012nm.