High power and highly efficient Nd:YAG laser emitting at 1123 nm

A diode-end-pumped continuous-wave (CW) Nd:YAG laser emitting at 1123 nm is realized efficiently in a 25-mm-long cavity. A composite Nd:YAG (cNd:YAG) crystal is selected as the gain medium. With an incident diode power of 26.1 W, an output power of up to 9.3 W is obtained, corresponding to an optical-to-optical conversion efficiency of 35.6%. The laser performances at 1123 nm are compared between composite Nd:YAG and common Nd:YAG crystals. The results show that composite Nd:YAG is a better choice for 1123-nm laser generations.     

Side-pumped continuous-wave Cr:Nd:YAG ceramic solar laser

To clarify the advantages of Cr:Nd:YAG ceramics rods in solar-pumped lasers, a fused silica light guide with rectangular cross-section is coupled to a compound V-shaped cavity within which a 7 mm diameter 0.1 at.% Cr:1.0 at.% Nd:YAG ceramic rod is uniformly pumped. The highly concentrated solar radiation at the focal spot of a 2 m diameter stationary parabolic mirror is transformed into a uniform pump radiation by the light guide. Efficient pump light absorption is achieved by pumping uniformly the ceramic rod within the V-shaped cavity. Optimum pumping parameters and solar laser output powers are found through ZEMAX^© non-sequential ray-tracing and LASCAD^© laser cavity analysis codes. 33.6 W continuous-wave laser power is measured, corresponding to 1.32 times enhancement over our previous results with a 4 mm diameter Nd:YAG single-crystal rod. High slope efficiency of 2.6 % is also registered. The solar laser output performances of both the ceramic and the single-crystal rods are finally compared, revealing the relative advantage of the Cr:Nd:YAG rod in conversion efficiency. Low scattering coefficient of 0.0018 cm^?1 is deduced for the ceramic rod. Heat load is considered as a key factor affecting the ceramic laser output performance.     

Diode-pumped 1123-nm Nd:YAG laser

We demonstrated a diode-pumped Nd:YAG laser with a plano-concave resonator. When the pump power is 1.57 W, the output power of 1123-nm laser is 132 mW at the temperature of 20 ℃, and the power change is less than 2% in an hour. A periodically poled LiNbOa (PPLN) was used as outer cavity frequency-doubling crystal and 561-nm laser was observed.     

Nd:LuYAG混晶1123 nm被动调Q激光器

文章报道了一个二极管激光抽运的1123 nm被动调Q激光器. 激光晶体为混晶Nd:LuYAG, 饱和吸收体选为Cr⁴⁺:YAG晶体. 在连续运转情况下, 最高输出功率为2.77 W, 对应的光-光转换效率为29.53%. 调Q运转时, 在9.38 W吸收抽运功率下, 最高输出功率为0.94 W. 脉冲宽度整体在105 ns左右. 在最高吸收抽运功率下, 1123 nm激光的输出重复频率为9.40 kHz, 对应的单脉冲能量可达100 μJ, 高于目前报道的单晶Nd:YAG 1123 nm单脉冲能量, 证明其在能量存储方面较单晶Nd:YAG更具优势. 另外, 据我们所知, 这是关于混晶Nd:LuYAG 1123 nm输出的首次报道.     

Generation of 2.1 W Continuous Wave Blue Light by Intracavity Doubling of a Diode-End-Pumped Nd：YAG Laser in a 30 mm LBO

A folded four-mirror cavity with a composite Nd：YAG rod is optimized to obtain high efficient cw 473nm blue output. The laser could operate stably in the region of the thermal-lens focal length from 20mm to 70mm. LBO is used for intracavity frequency doubling of the 946nm transition of Nd：YAG and the optimum LBO length is investigated. A maximum output power of 2.1 Win the blue spectral range at 473nm is achieved with 30-mm-long LBO, corresponding to an optical conversion efficiency of 9.1%.     

All solid-state CW orange-red laser at 620 nm

We report for the first time a continuous-wave (CW) orange-red radiation at 620 nm by intracavity sum-frequency generation of 1085-nm Nd:YVO₄ laser and 1444-nm Nd:YAG laser. Using type-II critical phase matching KTP crystal, 620-nm orange-red laser was obtained by 1085- and 1444-nm intra-cavity sum-frequency mixing, and output power of 223 mW was demonstrated. At the output power level of 223 mW, the output power stability is better than 3% and laser beam quality M ² factor is 1.32.     

A tunable corner-pumped Nd:YAG/YAG composite slab CW laser

A corner-pumped Nd:YAG/YAG composite slab continuous-wave laser operating at 1064 nm,1074 nm,1112 nm,1116 nm,and 1123 nm simultaneously and a laser that is tunable at these wavelengths are reported for the first time.The maximum output power of the five-wavelength laser is 5.66 W with an optical-to-optical conversion efficiency of 11.3%.After a birefringent filter is inserted in the cavity,the five wavelengths can be separated successfully by rotating the filter.The maximum output powers of the 1064 nm,1074 nm,1112 nm,1116 nm,and 1123 nm lasers are 1.51 W,1.3 W,1.27 W,0.86 W,and 0.72 W,respectively.     

219.3 W CW diode-side-pumped 1123 nm Nd:YAG laser

We demonstrate a high power continuous wave (CW) diode-side-pumped Nd:YAG laser operating at 1123 nm with a plano-plano configuration. By means of precise coating, a single 1123 nm wavelength is achieved. Under the pump power of 1080 W, an output power of 219.3 W is obtained, which corresponds to an optical-optical conversion efficiency of 20.3%. To the best of our knowledge, this is the highest output power for CW 1123 nm laser based on Nd:YAG crystal.     

660 nm单一波长Nd:YAG陶瓷激光器

 针对陶瓷晶体1319 nm的谱线设计了适合的谐振腔腔镜膜系参量,采用激光二极管列阵侧向抽运掺杂1.1at%、Φ3×50 mm的Nd:YAG陶瓷,利用色散棱镜及KTP晶体Ⅱ类匹配腔内倍频,研制了一台660 nm单一波长输出的高重频Nd:YAG陶瓷红光激光器.根据陶瓷晶体的热透镜焦距设计了谐振腔的各个参量,在重复频率为1000 Hz、单脉冲抽运能量约144 mJ时,获得了3.9 mJ的660 nm脉冲激光输出,总的光-光转换效率为2.71%.为进一步研究大功率、高效率的陶瓷红光激光器奠定了基础.     

670nm电光调Q陶瓷激光器

为了进一步研究Nd∶YAG陶瓷激光器的红光波段,研制了一台重复频率为1 000 Hz的670 nm电光调Q Nd∶YAG陶瓷激光器.采用三个激光二极管列阵侧面抽运掺杂浓度为1.1at%、尺寸为Φ3×50 mm2的Nd∶YAG陶瓷晶体,根据实验测量的陶瓷晶体热透镜焦距,优化设计了折叠腔的各个参量,并对陶瓷晶体及倍频晶体热...     

Continuous-wave, 15.2 W diode-end-pumped Nd:YAG laser operating at 946 nm

A high-power continuous-wave (cw) Nd:YAG laser operating at 946 nm by utilizing a quasi-three-level transition is reported. The laser consists of a composite Nd:YAG rod end pumped by a fiber-coupled diode laser and a simple plane-concave cavity. At an incident pump power of 40.2 W, a maximum cw output of 15.2 W at 946 nm is obtained, achieving a slope efficiency of 45%. To the best of our knowledge, this is the highest output at 946 nm ever generated by diode-pumped Nd:YAG lasers. In addition, at an incident pump power of 15.2 W, a 1.25 W blue output at 473 nm is achieved with a simple compact three-element cavity and a type-I lithium triborate (LiB(3)O(5)) crystal as a frequency doubler.     

39.5% conversion of low-power Q-switched Nd:YAG laser radiation to 266 nm by use of a resonant ring cavity

A simple ring cavity consisting of mirrors reflecting at the second harmonic is used to generate the fourth harmonic of low-power Q-switched Nd:YAG laser pulses. A large beam waist of 1 mm minimized the effects of double refraction and thermal loading of the nonlinear crystals. By simulating the low-power pulses with a small portion of the output from a 30-Hz flash-lamp-pumped Q-switched Nd:YAG laser, we obtained IR-UV energy conversion as great as 39.5% to yield 84-mW average power at 266 nm from 213 mW of single-mode 1064-nm radiation.     

Study on CW Nd:YAG infrared laser at 1319 nm

A continuous wave (CW) Nd:YAG infrared laser at 1319 nm is reported in this paper. The energy level of 1319-nm wave was analyzed. The repression of 1064-nm lasing and enhancement of 1319-nm output power were discussed. Mirror coating and cavity structure were studied and a maximum CW output power of 43 W at 1319 nm was achieved in experiments.     

High-power near diffraction-limited 1 064-nm Nd:YAG rod laser and second harmonic generation by intracavity-frequency-doubling

We present a near diffraction-limited 1 064-nm Nd:YAG rod laser with output power of 82.3 W(M~2≈1.38). The power fluctuation over two hours is better than±1.1%.Pulsed 1064-nm laser with an average power of 66.6 W and pulse width of 46 ns are achieved when the laser is Q-switched at a repetition rate of 10 kHz.The short pulse duration stems from the short cavity as well as the high-gain laser modules. Using intracavity-frequency-doubling,a 35.0-W near diffraction-limited 532-nm green laser(M~2≈1.32) is achieved with a pulse width of 43 ns.     

Highly efficient diode side-pumped Nd:YAG ceramic laser with 210 W output power

We developed a highly efficient diode side-pumped Nd:YAG ceramic laser with a diffusive reflector as an optical pump cavity. A maximum output power of 211.6 W was obtained with an optical-to-optical conversion efficiency of 48.7%. This corresponds to the highest conversion efficiency in the side-pumped ceramic rod. Thermal effects of the Nd:YAG ceramic rod were analyzed in detail through the measurements of laser output powers and beam profiles near the critically unstable region. A M² beam quality factor of 18.7 was obtained at the maximum laser output power.     

60 W yellow laser at 561 nm by intracavity frequency doubling of a diode-pumped Q-switched Nd:YAG laser

A high-power yellow laser was achieved by intracavity frequency doubling of a diode-pumped Nd:YAG rod laser. A solid etalon was inserted into the resonator to implement efficient operation of the low-gain single line at 1123 nm transition. By using a LBO crystal inside the cavity as the frequency doubler, the maximum output power of the 561 nm yellow laser was obtained to be as high as 60.3 W with a pulse repetition frequency of 6 kHz, corresponding to an optical-to-optical conversion efficiency of about 6.1%. The output power fluctuation of the yellow laser was measured to be better than 3% in half an hour.     

1.15 kW连续波全固态Nd:YAG激光器

研制了五组双线二极管列阵侧面泵浦Nd: YAG棒的高效率、高功率激光头。将一块90° 石英旋光片插入两个这样的激光头中间并置入热近非稳对称平平腔，产生了1157 W高光束质量（M2 ~ 39）1064 nm连续波输出，据我们所知，这是侧面泵浦双棒Nd: YAG激光器产生的最高功率。     

Highly efficient Nd:YAG/LBO laser at 473 nm under direct 885-nm diode laser pumping

<正>In diode pumped Nd:YAG lasers,the quantum defect is the most important parameter determining the thermal load of the laser crystal,which can be dramatically reduced by pumping directly into the upper laser level.A compact folded three-mirror cavity with a length of 105 mm is optimized to obtain a highly efficient 473-nm laser.When the absorbed pump power(with 15.8-W incident pump power) at 885 nm into Nd:YAG is 10 W,a continuous-wave 473-nm blue laser as high as 2.34 W is achieved by LBO intra-cavity frequency doubled.The optical-to-optical conversion efficiency is 14.8%.To the best of our knowledge, this is the highest efficiency at 473 nm by an intra-cavity doubled frequency Nd:YAG laser.     

LD端面泵浦Cr4:YAG被动调Q激光器输出特性研究

对激光二极管端面泵浦Cr⁴⁺:YAG被动调QNd:YAG激光器输出特性进行了实验研究.实验研究发现,激光器输出功率及脉冲重复频率随谐振腔长度增大而增大.为解释这一实验现象,测量了泵浦光斑在激光晶体内尺寸,同时计算了激光晶体及Cr⁴⁺:YAG晶体内的基模激光光斑半径随谐振腔长度变化.分析结果表明:激光晶体内泵浦光斑尺寸远小于激光晶体内基模光斑半径,腔模间交叠效率较低;当腔长增加时,激光晶体内的基模激光光斑减小,腔模间交叠效率增加,从而导致输出功率及脉冲重复频率随腔长增加而增加;另外,Cr⁴⁺:YAG晶体内光斑半径也随谐振腔长度减小,引起Cr⁴⁺:YAG晶体漂白时间缩短,导致脉冲重复频率随腔长增加而增加.     

High power CW diode-side-pumped Nd:YAG rod laser

We report on the characterization of a diode-side-pumped Nd:YAG rod laser operating at high CW output power. A four-fold pump configuration is designed and the pump light is directly coupled into the Nd:YAG rod without the help of any cylindrical lenses. The distribution of pump light in the Nd:YAG rod has been calculated by using ray tracing program. The thermal lens effect of the Nd:YAG rod has been experimentally measured. A maximum output power of 800 W at 1064 nm in multimode operation is obtained for a pump power of 2400 W with 33% optical-optical efficiency. At the same time, the maximum beam parameter product of 25 mm·mrad is achieved.