Nd:YAG陶瓷与单晶4F3/2–4I13/2跃迁的弱谱线多波长激光性能对比

报道了基于半导体激光端面抽运Nd:YAG的⁴F_3/2–⁴I_13/2 跃迁的弱谱线多波长激光输出. 实验对比了透明陶瓷与单晶材料的激光输出特性, 表明透明陶瓷和单晶材料荧光谱强度的略微差异, 导致了多波长输出时相同两个波长之间的激光强度比在两种材料中的差异. 基于两种耦合输出镜片, 激光阈值都在2 W左右. 在13.5 W的抽运功率下, 基于Nd:YAG透明陶瓷获得了输出功率4.05 W、强度比1 :2的1338与1356 nm双波长激光和输出功率3.65 W、强度比13 : 1的1356与1414 nm 双波长激光, 斜率效率分别达33.9% 和31.9%.     

Dual-wavelength bandwidth-narrowed output of a high-power diode laser using a simple external cavity

Using an external cavity consisting of an etalon and a mirror, dual-wavelength operation of a high-power broad-area multi-stripe diode laser is achieved. The reflection of the etalon is used as the output beam of the system. The free-running bandwidth of the laser diode is about 2.0 nm. At dual-wavelength operation, the bandwidth of each wavelength component is narrowed to about 0.07 nm, while the space between them is 1.65 nm, determined by the FSR of the etalon. We obtain an available dual-wavelength output power of 2.0 W at the drive current of 6.5 A. The power ratio of the components at two different wavelengths can be changed by changing the temperature of the diode laser. To tune the wavelength of the dual-wavelength output, the temperature of the laser diode and the tilt angle of the etalon are changed simultaneously PACS 42.55.Px; 42.60.Fc; 42.60.Da     

An All-Solid-State Tunable Dual-Wavelength Ti：Sapphire Laser with Quasi-Continuous-Wave Outputs

A high power dual-wavelength Ti：sapphire laser system with wide turning range and high efficiency is described, which consists of two prism-dispersed resonators pumped by an a11-solid-state frequency-doubled Nd：YAG laser. Tunable dual-wavelength outputs, with one wavelength range from 750nm to 795nm and the other from 80Ohm to 850nm, have been demonstrated. With a pump power of 23 W at 532nm, a repetition rate of 6.5kHz and a pulse width of 67.6ns, the maximum dual-wavelength output power of 5.6 W at 785.3nm and 812.1 run, with a pulse width of 17.2ns and a line width of 2nm, has been achieved, leading to an optical-to-optical conversion efficiency of 24.4%.     

双波长Yb∶YAG连续激光理论及实验研究

报道了Yb∶YAG双波长激光振荡阈值的理论结果,实验获得了连续双波长激光输出.实验中,采用紧凑的平凹腔结构、940nm光纤耦合LD端面泵浦方式,Yb∶YAG晶体作为激光晶体,采用10%、15%和20%的输出耦合镜,分别实现了单波长和双波长激光输出,在最高泵浦功率为20 W时,输出耦合率分别为10%、20%,最高获得3.94W的1 050nm激光和3.40 W的1 030nm激光,对应的光光转换效率分别为19.7%和17.0%;当输出耦合率为15%、泵浦功率为11.7 W时,获得0.79 W的双波长激光,对应的光光转换效率为6.8%,功率比为1∶1.3,通过光栅光谱仪测量得到双波长谱线中心分别为1 030.31nm和1 047.50nm;当1 030nm激光功率为3.0 W时,30min内输出功率RMS稳定性优于0.18%.该实验结果与理论分析相吻合,可应用于设计稳定可靠的掺Yb双波长激光器.     

Efficient all solid-state CW yellow-green light source

A dual-wavelength continuous-wave (CW) diode-pumped Nd:YAG laser that generates simultaneous laser action at the wavelengths 946 nm and 1319 nm is demonstrated. A total yellow-green output power of 2.33 W for the dual-wavelength was achieved at the incident pump power of 18.2 W. Furthermore, intracavity sum-frequency mixing at 946 and 1319 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 340 mW at 551 nm.     

LD side-pumped Nd:GGG CW laser operating at 1110 and 1105 nm dual wavelengths and 1110 nm single wavelength

A diode-side-pumped continuous-wave Nd:GGG laser operating at dual-wavelength (1110 and 1105 nm) and single wavelength of 1110 nm is demonstrated for the first time. The maximum output power of the 1110 and 1105 nm dual-wavelength operation is 13.2 W. By adjusting the orientation of an insertion mirror, the relative intensities of the two wavelengths can be changed. Thus single wavelength operation at 1110 nm is obtained, and the output power is 9.6 W.     

Characteristics of Nd：GdVO4 Laser with Different Nd-Doping Concentrations

We report the properties of a compact diode-pumped continuous-wave Nd：GdV04 laser with a linear cavity and different Nd-doped laser crystals. In a 0.2at.% Nd-doped Nd：GdVO4 laser, 1.54 W output laser power is achieved at 912nm wavelength with a slope efficiency of 24.8% at an absorbed pump power of 9.4W. With 0.3at.% Nd-doping concentration, we can obtain the either single-wavelength emission at 1064nm or 912nm or the dual-wavelength emission at 1064nm and 912nm by controlling the incident pump power. From an incident pump power of 11.6 W, the 1064nm emission between ^4Fa/2 and ^4I11/2 is suppressed completely by the 912nm emission between ^4Fa/2 and ^4I9/2. We obtain 670 mW output of the 912nm single-wavelength laser emission with a slope efficiency of 5.5% by taking an incident pump power of 18.4 W. Using a Nd：GdV04 laser with 0.4at.% Nd-doping concentration, we obtain either the single-wavelength emission at 1064nm or the dual-wavelength emission at both 1064nm and 912nm by increasing the incident pump power. We observe a strong competition process in the dualavelength laser.     

激光二极管抽运Nd:YV04和频黄光激光器的理论及实验研究

为了达到最佳和频593 nm黄色激光输出,采用激光二极管(LD)端面抽运Nd:YVO4晶体,根据四能级系统的速率方程理论,建立了空间相关的两波长激光运转速率方程模型,由此导出两波光子数表达式.对LD端面抽运Nd:YVO4/KTP三镜复合腔结构的腔内和频黄光激光器,在满足参与和频的两基频光光子数密度相等的条件下,理论上得到了谐振腔的各个参数.实验比较了在满足两波光子数密度相等和两波振荡阈值相等两种情况下激光器输出的593 nm黄色激光功率.在抽运功率为12 W时,二种情况下分别得到了410 mW和340 mW的黄光输出,光一光转换效率分别为3.4%和2.8%.由此可见,在满足两波光子数密度相等的条件下可以得到更高转换效率的和频黄光输出.     

Simultaneous dual-wavelength CW operation using F3/2–I13/2 transitions in Nd:YVO4 crystal

We experimentally demonstrate a dual-wavelength continuous wave (CW) Nd:YVO₄ laser simultaneously operating at 1342 and 1386 nm. A total output power of 439 mW is achieved when the laser is diode-end-pumped at an incident pump power of 2.4 W, indicating a slope efficiency of 35.6%. To the best of our knowledge, it is the first time that simultaneous dual-wavelength CW operation at 1342 and 1386 nm is reported.     

Nd:YVO4复合腔激光器双波长激光输出及腔内和频研究

 采用两个重叠的共线支腔构成的三镜复合腔,实现LD泵浦的Nd:YVO₄激光器的1 064 nm和1 342 nm双波长激光运转。根据双波长振荡阈值相等条件,数值计算了1 064 nm支腔和1 342 nm支腔的腔长、支腔的输出耦合镜透过率之间的关系。合理选择两个支腔的参数,当泵浦功率13 W时,获得1 064 nm激光功率1.59 W,1 342 nm激光功率1.17 W的双波长激光输出。在满足腔内1 064 nm 和1 342 nm双波长光子数密度相等的条件下,计算了腔内和频的复合腔Nd:YVO4激光器的腔参数。采用Ⅱ类临界相位匹配KTP晶体作为和频器件,当808 nm泵浦光功率为12 W时,获得340 mW的和频593 nm激光输出。     

Simultaneous dual-wavelength Q-switched Nd:YAG laser operating at 1.06 μm and 946 nm

Considering the reabsorption loss of the quasi-three level system and the unsaturable loss of the saturable absorber, we obtained the operating condition of a diode-pumped simultaneous dual-wavelength Q-switched Nd:YAG laser operating at 1.06 μm and 946 nm. The dual-wavelength pulsed laser was realized successfully through adaptive coating design of the cavity mirrors. As much as 1.6 W total average output power of the dual-wavelength at 1.06 μm and 946 nm was achieved at the incident pump power of 14.2 W with an optical conversion efficiency of 11.3%.     

High-power red-green-blue laser light source based on intermittent oscillating dual-wavelength Nd:YAG laser with a cascaded LiTaO3 superlattice

We demonstrate a high-power red-green-blue laser source based on the quasi-phase-matching and intermittent oscillating dual-wavelength laser technique. A cascaded LiTaO3 superlattice was used to achieve the generation of red light at 660 nm, green light at 532 nm, and blue light at 440 nm to obtain the output of red-green-blue laser light from a diode-side-pumped Q-switched intermittent oscillating dual-wavelength Nd:YAG laser. The average output power of red-green-blue of 1.01 W was achieved under the total fundamental power of 5.1 W, which corresponds to the conversion efficiency of 20%.     

Compact 584-nm light source based on sum-frequency mixing of diode pumped Nd:YLF lasers

A dual-wavelength continuous-wave (CW) diode end-pumped Nd:YLiF₄ (Nd:YLF) laser that generates simultaneous laser action at the wavelengths 1047 and 1321 nm is demonstrated. A total output power of 350 mW for the dual-wavelength was achieved. Furthermore, intracavity sum-frequency mixing at 1047 and 1321 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 34 mW at 584 nm.     

Continuous wave dual-wavelength Nd:YVO_4 laser working at 1064 and 1066 nm

We demonstrate a continuous-wave(CW) dual-wavelength Nd:YVO4laser working at 1064 and 1066 nm simultaneously. The method of Nd:YVO4crystal angle tuning is used to balance the ratio of the stimulated emission cross sections of the two wavelengths, leading to the realization of a simultaneous dual-wavelength operation from only one laser. The experimental results show that at a 2.85 W pump power, the maximum output powers at wavelengths of 1064 and 1066 nm are 0.55 and 0.54 W, respectively. The linear resonate cavity is as short as 10 mm, which gives the laser the advantages of a miniature configuration and low threshold. Such a dual-wavelength laser can be very attractive for the development of compact THz sources based on difference frequency generation.     

Continuous-wave dual-wavelength operation of a diode-end-pumped Nd:LuVO<Subscript>4</Subscript> laser

A dual-wavelength continuous-wave (CW) diode-pumped Nd:LuVO₄ laser that generates simultaneous laser action at the wavelengths 1066 and 1343 nm is demonstrated. A total dual-wavelength output power of 2.58 W was achieved at the incident pump power of 18.2 W. Furthermore, intracavity sum-frequency mixing at 1066 and 1343 nm was then realized in a LBO crystal to reach the yellow range. We obtained a total CW yellow output power of 830 mW at 594 nm.     

Diode-pumped Nd:YVO<Subscript>4</Subscript>-LBO laser at 544 nm based on intracavity sum frequency generation

A dual-wavelength continuous-wave (CW) diode-pumped Nd:YVO₄ laser that generates simultaneous laser action at the wavelengths 914 and 1342 nm is demonstrated. A total dual-wavelength output power of 1.79 W was achieved at the incident pump power of 18.2 W. Furthermore, intracavity sum-frequency mixing at 914 and 1342 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 212 mW at 544 nm.     

Quasi-three-level neodymium-doped yttrium aluminum garnet laser emitting at 885 nm

We present a diode-pumped quasi-three-level neodymium-doped yttrium aluminum garnet (Nd:YAG) laser at 885?nm, based on the F_3/24-I_9/24 transition, generally used for a 946?nm emission. Combined with polarization components (Nd:YAG), the electro-optical crystal KH₂PO₄ (KDP) formed a Lyot filter in the cavity and compressed the available gain bandwidth. With an incident pump power of 9.2?W, a 714?mW continuous-wave (CW) output at 885?nm was achieved, and the optical-to-optical efficiency was 7.8%. With an adjustable voltage applied to the KDP crystal, the laser wavelength could be tuned from 885?nm to 884?nm. A simultaneous dual-wavelength Nd:YAG laser at 885?nm and 884?nm was also realized by adjusting the free spectral range of the Lyot filter. To our knowledge, it is the first study that has realized the tuning between the 884 and 885?nm lines and the simultaneous dual-wavelength CW laser operation at 885?nm and 884?nm.     

可用于产生微波信号的间隔可调双波长光纤激光器

为了获得不同间隔双波长信号输出,提出一种基于受激布里渊效应产生双波长激光的实验装置,利用不同间隔双波长输出信号进行拍频实验可获得可调的微波信号输出;利用一段10 km长普通单模光纤（SMF）作为布里渊增益介质,一个线宽为5 kHz分布反馈激光器（DFB）作为布里渊抽运源,一段未泵浦的保偏掺铒光纤用作饱和吸收体抑制边模,通过改变未泵浦保偏掺铒光纤的长度,可获得不同间隔输出的双波长光纤激光器,实验获得波长间隔为0.170 nm和0.085 nm的激光信号输出,分别对应20 GHz和10 GHz的微波信号。     

High efficiency, dual-wavelength fibre Raman pump laser for U-band fibre Raman amplifiers

A dual-wavelength, continuous wave, high efficiency fibre Raman ring laser for pumping U-band (1625–1675 nm) fibre Raman amplifiers is demonstrated. Two fibre Bragg gratings were used as wavelength-selective elements resulting in lasing lines at 1529.7 and 1558.7 nm with respective maximum powers of 209.0 and 390.9 mW. A simple U-band Raman amplifier was constructed to test the dual-wavelength pump laser and on:off gain with a peak of 7.3 dB and a 3-dB bandwidth of 73 nm was obtained.     

cw dual-wavelength operation of a diode-end-pumped Nd:YVO4 laser

A dual-wavelength continuous wave (cw) diode-end-pumped Nd:YVO₄ laser that generates simultaneous laser action at the wavelengths 1064 nm and 1342 nm is demonstrated. The optimum oscillation condition for the simultaneous dual-wavelength operation in a diode-end-pumped solid-state laser has been derived. The relationship between the laser cavity and the output stability is also studied. Experimental results show that the stability of the output power at the two wavelengths could be enhanced by use of a three-mirror cavity. Received: 26 August 1999 / Revised version: 11 October 1999 / Published online: 23 February 2000