Flashlamp-pumped YAG:Nd+3laser action at kilohertz rates

Laser action at high repetition rates with flashlamp pumping has been achieved in a YAG:Nd³⁺laser rod. With the resonant charging techniques used in the experiments, the repetition rate is limited by the heating of the laser rod.     

Parasitic noise on the output of a CW YAG:Nd+3laser

An experimental investigation was conducted to reduce the parasitic noise appearing on the output of a 6-W CW YAG:Nd⁺³laser. Initially, low-frequency fluctuations as high as 30 percent and relaxation oscillation bursts exceeding 80 percent of the CW power level were present. Low-frequency modulation was reduced by the addition of an active feedback loop to control lamp current. Relaxation oscillations were determined to be influenced by laser rod cooling, pump-lamp aging, vibration, and intracavity optical interface quality. At the conclusion of the program, low-power fluctuations and relaxation oscillation excursions did not exceed 2 percent.     

Periodic multiplate resonant reflector for a YAG: Nd3+laser at 1.318 µ

A periodic resonant reflector with thin air intervals is designed for a YAG:Nd³⁺laser in order to achieve emission of a line at 1.318 μ by suppressing the well-known line at 1.064 μ for reasons of laser safety.     

环形腔YAG:Nd~(3 )激光器

在带有附加反馈镜的YAG:Nd~(3 )环形腔中,得到了定向比为30的单向输出。谱线宽度较之驻波腔压缩了十倍,输出功率并不降低。对其振荡时间特性提出了新的见解。     

Self-Q-switched Nd3+: YAG and ruby lasers

Self-Q-switched operation of Nd³⁺: YAG lasers at 77°K and ruby lasers at 300 and 77°K pumped by the 5145-Å output of a pulsed argon ion laser is described. Self-Q-switched operation was obtained 1) by static mirror misalignment and 2) by static misalignment of the filament of the pumped laser material with respect to the mirror resonator axis. An output that consisted of a single giant pulse could be obtained for ruby by either method; for Nd³⁺: YAG, the output always consisted of one or more giant pulses and characteristic relaxation oscillations.     

Carrier-frequency-controlled gigabit pulse generation with a Nd3+: YAG laser

Optical pulses up to 1.25 Gbit/s were obtained with a Nd³⁺:YAG laser by multiple mode locking. The carrier frequency of mode-locked pulses was tuned through several tens of gigahertz by tilting an intracavity tuning etalon. Some detuning effects in forced mode locking will be also presented.     

Thermal effects of a continuously pumped Nd3+:YAG laser

Thermal effects in a Nd:YAG laser rod, which is pumped continuously by tungsten iodine lamps, are described. Measurements using a 0.6328-μman probe beam yielded temperature distribution in and at the boundary of the rod. The results of birefringence and focal length are consistent with theoretical treatments, if an effective heat conversion coefficient peculiar to the apparatus is assumed. The resonance condition of an optical resonator containing a rod exhibiting focusing effect is discussed.     

连续Nd~(3 ):YAG激光对视网膜损伤阈值的研究

连续Nd~(3 ):YAG激光照射青紫蓝灰兔眼100只,1000个照射点,求得照射时间平均1.02s及0.12s,检眼镜可见视网膜损伤阈值,其ED_(50)分别为角膜平均入射2.52W/cm~2及5.42W/cm~2.     

Response of a CW Nd3+:YAG laser to sinusoidal cavity perturbations

Sinusoidal perturbations are applied to the resonator of a CW Nd³⁺:YAG laser to study the response of the system. Two kinds of resonances are observed. The resonant AM mode exhibits a sinusoidal modulation in the output and its frequency is determined by the pumping power and cavity losses. The spiking mode shows a train of regular pulses and its frequency is constant. Nonlinear coupled rate equations are solved to show solutions in good agreement with the experimental observations. The effect of nonresonant perturbation on the output is also presented.     

用于显微光谱分析的光再生电光调Q Nd~(3 ):YAG激光器

将不稳定光学谐振腔光再生电光调Q Nd~(3 ):YAG激光器用于显微光谱分析。使激光稳定性在自由振荡情况下相对均方误差达0.92％,调Q时<5％,取样直径5～450微米,对样品的适应性和可靠性有较大提高。     

高稳定主被动锁模重复率Nd~(3 ):YAG激光器

本文介绍的是利用可饱和吸收体五甲川与100兆赫驻波型声光调制器联合运行的主被动锁模重复率Nd~(3 ):YAG激光器。在正常运转的情况下,它是借助于声光调制“窗口”有效地克服“尖峰”群的随机竞争,从而获得既稳又窄的光脉冲输出的。 通过下列途径和措施增强了稳定性和多功能性: 1.采用频率合成式高频大功率声光驱动源,有效地克服因环境温度变化、介质加工精度等因素造成的声光街射效率下降和消失的特点。 2.采用机械组合式的一体化染料盒,有效地克服籽腔振荡。     

Separation of mode-locked states in the intracavity phase-modulated Nd3+:YAG laser

It has been observed that the frequency difference between the two modes for the mode-locked Nd³⁺:YAG laser by synchronous internal phase modulation depends on the pumping power and is several hundreds of kilohertz for a realistic pumping power. By finely tuning the mode-locking frequency, the two modes can be excited separately.     

Oscillation of the 1.833-µ line in Nd3+:YAG

This correspondence reports oscillation of the⁴F_{32} rightarrow⁴I_{15/2}, 1.833-mutransition in Nd³⁺:YAG. PeakQ-switched output powers of 10 kW at 50 pps have been obtained.     

双掺(Ce~(3+)、Nd~(3+)):YAG晶体对撞脉冲锁模的研究

一、引 言 新晶体双掺(Ce~(3+)、Nd~(3+)):YAG是一种具有高转换效率的激光增益介质~[1],它利用Ce~(3+)、Nd~(3+)的敏化途径提高激光效率。晶体中的Ce~(3+)离予通过辐射和非辐射二种方式向Nd~（3+）转     

Cr3+→Nd3+ energy transfer and Nd3+ laser action studies of La3Ga5SiO14:Cr3+,Nd3+ co-doped crystal

Energy transfer between Cr³⁺ and Nd³⁺ ions has been investigated in the 4.2-300-K temperature range by using steady-state and site-selective time-resolved laser spectroscopy. Radiative and nonradiative energy transfer has been studied from the time-resolved emission spectra and the donor fluorescence decays. The transfer efficiency was calculated as a function of temperature by using the Cr³⁺ lifetimes of the single doped and co-doped samples. Laser experiments were carried out in a diffusive cavity by pumping a co-doped rod 54 mm long and 5 mm in diameter with xenon flashlamps. The laser spectral emission shows a complex structure which varies as a function of pump energy. The temporal evolution of the laser spectrum is discussed in terms of a simple four-level spectral rate-equation laser model which takes into account the existence of two main broad Nd³⁺ site distributions with a large spectral overlap     

Doubly Passively Self-Q-Switched Cr4+:Nd3+:YAG Laser With a GaAs Output Coupler in a Short Cavity

By using a GaAs as both an output coupler and a saturable absorber, we present a doubly passively self-Q-switched Cr⁴⁺:Nd³⁺:YAG laser in a short cavity for the first time to our knowledge. This laser can generate more symmetric pulse shape and shorter pulsewidth in comparison with the solely self-Q-switched Cr⁴⁺:Nd³⁺:YAG laser. The output pulse energy and peak powers are higher than those in our previous doubly passively Q-switched lasers. By considering the Gaussian spatial distribution of the intra-cavity photon density and the free carrier absorption (FCA) in GaAs wafer, a set of modified rate equations have been introduced to describe the performances of the doubly Q-switched Cr ⁴⁺:Nd³⁺:YAG laser with GaAs coupler. The numerical solutions of the equations and the experimental results are found to agree with each other very well. The effect of FCA process in GaAs wafer has been discussed and proved to play an important role in the pulse compression and symmetry     

1.3 μm Nd3+:YAG脉冲激光器的特性与设计

对Nd3+:YAG 1.3 μｍ波段的脉冲激光器进行了特性分析和实验研制。尤其是输出腔镜的最佳透过率的选择,谐振腔类型的选择,以及与1.06 μm脉冲器件的比较和改造。文中给出了最佳透过率,1.32 μm,1.34 μm两波长激光能量与输出镜透过率的关系等实验数据。     

FTIR-Q开关的YAG:Nd~(3 )激光器巨脉冲特性的研究

根据速率方程,解出了FTIR-Q开关下YAG:Nd~(3 )的激光输出特性。给出了FTIR-Q