双棒串接Nd3+∶YAG激光器

根据测量的单根 Nd3+∶ YAG棒的热焦距 ,利用 ABCD传输矩阵计算了双棒串接的几种腔型的稳定参量 ,给出了能够满足高功率、高稳定性激光输出的稳定腔型 ,实验结果与理论分析基本相符     

双棒串接Nd:YAG激光器的稳区分析和实验研究

用传输矩阵法理论分析了在含热致双折射补偿和不含热致双折射补偿两种情况下,r偏振和偏振对双棒串接激光器谐振腔稳区的影响.选用低掺杂浓度的Nd:YAG棒,实验上用含90°石英旋光片的双棒对称平行平面短腔获得了最佳实验结果.1 064 nm激光最高输出功率达482.3 W,对应光-光转换效率为40.2%.     

双棒串接Nd∶YAG激光器的稳区分析和实验研究

用传输矩阵法理论分析了在含热致双折射补偿和不含热致双折射补偿两种情况下,r偏振和Ф偏振对双棒串接激光器谐振腔稳区的影响.选用低掺杂浓度的Nd∶YAG棒,实验上用含90°石英旋光片的双棒对称平行平面短腔获得了最佳实验结果.1064nm激光最高输出功率达482.3W,对应光-光转换效率为40.2%.     

双棒串接Nd∶YAG激光器的稳区分析和实验研究

用传输矩阵法理论分析了在含热致双折射补偿和不含热致双折射补偿两种情况下,r偏振和偏振对双棒串接激光器谐振腔稳区的影响.选用低掺杂浓度的Nd∶YAG棒,实验上用含90°石英旋光片的双棒对称平行平面短腔获得了最佳实验结果.1 064 nm激光最高输出功率达482.3 W,对应光-光转换效率为40.2％.     

高平均功率六棒串接脉冲Nd:YAG激光器

报道了一种腔内六棒串接的脉冲Nd:YAG激光器。采用44矩阵对晶体棒失调角度对谐振腔光轴的影响进行了理论分析,给出了六棒串接脉冲激光器中晶体棒失调角度的允许范围。在串接实验中,谐振腔采用对称平平腔结构,通过调整每根晶体棒的失调角度到允许范围内,实现了六棒串接脉冲Nd:YAG激光器。在输入电功率86 kW,占空比17%时,获得了平均功率3 018 W的脉冲激光输出,峰值功率17.75 kW,最高单脉冲能量为66 J,光束参数乘积为26.3 mmmrad,电光转换效率3.5%,长时间工作不稳定性小于2%。     

高平均功率六棒串接脉冲Nd:YAG激光器

报道了一种腔内六棒串接的脉冲Nd:YAG激光器。采用44矩阵对晶体棒失调角度对谐振腔光轴的影响进行了理论分析,给出了六棒串接脉冲激光器中晶体棒失调角度的允许范围。在串接实验中,谐振腔采用对称平平腔结构,通过调整每根晶体棒的失调角度到允许范围内,实现了六棒串接脉冲Nd:YAG激光器。在输入电功率86 kW,占空比17%时,获得了平均功率3 018 W的脉冲激光输出,峰值功率17.75 kW,最高单脉冲能量为66 J,光束参数乘积为26.3 mmmrad,电光转换效率3.5%,长时间工作不稳定性小于2%。     

四棒串接连续灯泵浦Nd:YAG大功率激光器

 报道了一种符合工业应用的四棒谐振腔连续Nd:YAG激光器。实验中采用对称放置方式四棒串接谐振腔得到2 105 W的平均功率输出，光束参数积24 mm·mrad，系统总光电转换效率达到3.5%。还对影响激光器工作的因素进行了理论分析。     

腔内双棒串接的基模动态稳定腔研究

为了获得大功率高亮度的激光光源,设计并实现了一种使用双棒串接的基模动态稳定谐振腔.通过补偿热致双折射效应以及合理地设计腔内参数,在使用闪光灯抽运的条件下获得了61W的基模连续输出.使用等效热透镜的方法分析了谐振腔参数对激光器性能的影响,解释了输出镜和全反镜的距离对激光器性能所起的不同作用.关键词：动态稳定腔双棒谐振腔模式     

多棒串接固体激光器谐振腔的研究

运用矩阵光学的方法对多棒串接固体激光器的谐振腔参数及其在平平腔时的热稳条件进行了研究,并计算了六棒串接平平腔固体激光器的稳定区.结果证明：多棒串接固体激光器的稳定区和非稳区相互间隔,在平平腔总腔长、激光棒数量n和棒间距L一定的条件下,当采用对称结构时(L₁=L₂),则谐振腔的每段稳定区均达到最大;且只要 平平腔满足L₁=L₂=L/2以及热焦距f在大于某个下限值f_m时,稳定性条件01<关键词：多棒串接固体激光器稳定区热稳条件     

二极管侧面抽运Nd:YAG/KTP腔内倍频百瓦级绿光激光器

为了获得百瓦级激光二极管侧面泵浦绿光激光器,设计了双棒串接、双声光调Q的Z型谐振腔结构.依据光束传输矩阵,通过软件模拟并计算了激光晶体内基模半径随屈光度的变化以及倍频晶体附近腔内光场在子午面和弧矢面内的分布情况,筛选出理想的谐振腔参数.在总泵浦功率1 080 W,声光调Q重复频率为10 kHz时,获得532 nm绿光最大平均输出功率为174.1 W,脉冲宽度为160 ns,光-光转换效率为16.1%,光束质量因子M2x＝9.63,M2y＝9.78.实验结果表明,使用双棒串接、双声光调制Z型腔结构,可以获得百瓦级高功率高光束质量532 nm绿光输出.     

Diffusion-limited energy transfer from Tb3+ → Nd3+ and Tb3+ → Ho3+ in DMSO

The energy transfer phenomenon has been studied from Tb³⁺ → Nd³⁺ and Tb³⁺ → Ho³⁺ in DMSO. A diffusion limited dipole-dipole mechanism of energy transfer is suggested for both systems. At high acceptor concentrations, P_da depends linearly on C² consistent with the Fong and Diestler theory of energy transfer. However, at low acceptor concentrations the observations of time evolutions of Tb³⁺ luminescence decay following flash excitation has enabled us to examine diffusion limited energy transfer from Tb³⁺ to Nd³⁺ and Tb³⁺ to Ho³⁺ in DMSO.     

Energy transfer from Tb3+ to Nd3+ in sodium borate glass

The mechanism of energy transfer between Tb and Nd in sodium borate glass has been examined at 80, 300 and 500 K. By the measurements of the concentration dependence of intensity and lifetime, it has been found that the transfer from the ⁵D₄ level of Tb is predominantly by dipole-dipole interaction at high Nd concentrations. At low Nd concentration, however, the interaction shows a linear dependence with concentration. This linear concentration dependence is attributable to energy migration in glass. Further, the ⁵D₄→⁷F₄ transition of Tb has also been found to be quenched by radiative transfer. The ⁵D₃ level of Tb is also quenched by dipole-dipole interaction.     

Magnetic properties of paramagnetically doped crystals Fe3+, Nd3+ and Ho3+ in various compounds

In this work we calculate the energy levels, wave functions and transition probabilities for a number of compounds whose crystal field parameters have been determined. We introduce a convergence criterion in the diagonalization of the Hamilton matrices dependent upon a self consistency test on the eigenvectors. This assures us of numerically accurate wave functions.First we calculated energy level and susceptibility differences in (Nd³⁺)PbMoO₄ dependent on the multiplicative constants θ_n, used with the published A_l^m to determine the crystal field parameters B_l^m, (B_l^m = θ_nA_l^M). Calculated energy levels as a function of external magnetic field strength and orientation are compared with experimental results for three different sets of published crystal field parameters, B_l^m, for (Fe³⁺)TiO₂. The ground state energy levels, and wave functions, have been calculated for the non-Kramers Ho³⁺ ion in the crystals PbMoO₄, LaCl₃ and HoCl₃. Easily distinguishable variations in the temperature dependence of the X_zz component of the susceptibility are found as a function of the host crystal. It is pointed out that susceptibility calculations, based upon measured crystal field parameters, in conjunction with subsequent susceptibility measurements, provide a good check on the validity of the crystal field parameters.     

Non-radiative energy transfer from Sm3+→Nd3+ in sodium borate glass

A study of energy transfer from optically excited Sm³⁺ to Nd³⁺ in borate glass has been performed. Contrary to the observations made by Cabezas and DeShazer, the Sm³⁺ → Nd³⁺ energy transfer has been observed as non-radiative. Energy transfer probabilities (P_da) and transfer efficiencies (η_T) have been calculated from our measurements of donor fluorescence intensity and decay times. The mechanism governing the transfer is electrostatic dipole-dipole in nature, contrary to the conclusions made by Nakazawa and Shionoya. At low acceptor (Nd³⁺) concentrations a linear dependence of P_da on acceptor concentration (C) has been observed which suggests the migration of excitation energy among donors. At high acceptor (Nd³⁺) concentration a plot of P_da vs (C_o + C)², where C_o is donor ion concentration, presents a linear dependence which is consistent with the Fong-Drestler theory of dipole-dipole energy transfer mechanism and interaction of one donor (Sm³⁺) with two acceptors (Nd³⁺).     

Charge transfer excitation of the Nd3+, Sm3+, Dy3+, Ho3+, Er3+ and Tm3+ emission in CaGa2S4

The excitation spectra of the Nd³⁺, Sm³⁺, Dy³⁺, Ho³⁺, Er³⁺ and Tm³⁺ emission in the sodium-compensated CaGa₂S₄ host lattice, a sulfide with wide band gap, contain an intense band below the absorption edge. Comparison of the energy of its maximum with thermodynamic data and correlations to Jørgensen's refined spin-pairing theory predictions allow one to ascribe this band to a charge transfer transition ending onto 4f orbitals. The irregular variation within the rare earth series contrasts with the monotonic variation of the absorption edge in stoichiometric rare earth sulfides (e.g. NaLnS₂), associated with interband transitions.     

On the behavior of Nd3+ in LaCl3

Various properties of Nd³⁺: LaCl₃ which are influenced strongly by the crystalline electric field (CF) have been studied in the intermediate coupling scheme. A satisfactory correlation among the diverse observed properties has been achieved with the CF of Crosswhite et al. The hitherto uncertain lattice contribution to the electric field gradient (EFG) at the nuclear site has been established quite precisely. Some interesting features in the magnetic and thermal behavior of Nd³⁺ are also predicted.     

Racah and Judd-Ofelt parameters for Pr3+, Nd3+, and Er3+ ions in a laser liquid

The values of the Slater-Condon (F₂, F₄, F₆), Racah (E¹, E², E³) and Lande ξ₄f coefficients the nephelauxetic ratio (β), the bonding parameter (σ), and the Judd-Ofelt intensity (T_λ) parameters have been calculated from the reported absorption spectra of Pr³⁺, Nd³⁺, and Er³⁺ ions in an aprotic solvent SeOCl₂ acidified with antimony pentachloride. The nature of the bonding is suggested to be covalent for praseodymium, neodymium and erbium ions in the laser liquid in view of the magnitude of the respective bonding parameters.     

Spectroscopic investigation of a new crystal： Nd^3＋,Yb^3＋：YVO4

The absorption and emission spectra of the YVO4 single crystal co-doped with 1 at.% Nd^3＋ and 1 at.% Yb^3＋ are investigated. The efficient Nd^3＋ → Yb^3＋ energy transfer and the back transfer （Yb^3＋ → Nd^3＋） are observed at room temperature. The fluorescence lifetime of the 4F3/2 level of Nd^3＋ in Nd,Yb：YVO4 is measured under 808 nm laser light excitation. The efficiency of Nd^3＋ → Yb^3＋ energy transfer in YVO4 is determined to be about 34%.     

1. 32μm Nd~(3 ): YAG Pulse Laser

Using specially coated mirrors, an output energy of 0.97 J at 1.32 μm from a Nd3 : YAG pulse laser is obtained with pumping energy of 66 J. The repetition rate is 1 pulse/sec and the slope efficiency is 1.7%. The repetition rate can be changed from 1 pulse/sec to 10 pulses/sec.