LD端面抽运Nd:YAG 1319/1338nm双波长激光器研究

从LD端面抽运固体激光器的激光阈值公式出发,建立了双波长激光同时振荡的阈值条件,理论计算了腔镜对于两个波长的透过率关系,实现了LD端面抽运Nd:YAG 1319nm/1338nm双波长激光连续和准连续输出.双波长激光连续输出功率可达6W,斜效率为30%;准连续输出功率在重复频率50kHz时可达4.75W,斜效率为24.73%,脉冲宽度为55.05ns;腔内插入布儒斯特片,在重复频率为50kHz时,双波长激光准连续线偏振输出功率可达2.22W,不稳定性小于0.52%,M² 关键词： 端泵Nd:YAG激光器 1319nm/1338nm双波长 声光调Q 太赫兹波     

LD端面抽运Nd:YAG 1319nm/1338nm双波长激光器研究

从LD端面抽运固体激光器的激光阈值公式出发，建立了双波长激光同时振荡的阈值条件，理论计算了腔镜对于两个波长的透过率关系，实现了LD端面抽运Nd:YAG 1319nm/1338nm双波长激光连续和准连续输出.双波长激光连续输出功率可达6W，斜效率为30%；准连续输出功率在重复频率50kHz时可达4.75W，斜效率为24.73%，脉冲宽度为55.05ns；腔内插入布儒斯特片，在重复频率为50kHz时，双波长激光准连续线偏振输出功率可达2.22W，不稳定性小于0.52%，M²     

Continuous-wave dual-wavelength operation of a diode-end-pumped Nd:GGG laser

A diode-end-pumped continuous-wave (CW) simultaneous dual-wavelength laser operation at 1062 and 1331 nm in a single Nd:GGG was demonstrated. A total output power of 1.08 W at the two fundamental wavelengths was achieved at the incident pump power of 18.2 W. The optical-to-optical conversion is up to 5.9% with respect to the incident pump power. To the best of our knowledge, this is first work on CW simultaneous dual-wavelength operation of a diode pumped Nd:GGG laser. The article is published in the original.)     

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.     

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 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.     

Efficient stable simultaneous CW dual-wavelength diode-end-pumped Nd :YAG laser operating at 1.319 and 1.338 μm

An efficient, stable diode-end-pumped simultaneous continuous-wave (CW) dual-wavelength laser operating at 1.319 and 1.338 μm in a Nd:YAG crystal has been demonstrated. A total output power of 6.3 W is achieved at an absorbed pump power of 15 W, with a slope efficiency of 43.5%. The instability of output power is less than 1%. With a type Ⅱ critical phase-matched KTP crystal inserted into the cavity as frequency doubler, a maximum output power of 200 mW in red region is acquired. In addition, a sixwavelength laser operation at 1.319 μm, 1.338 μm, 1.356 μm, 659.5 nm, 669 nm, and 678 nm is observed.     

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.     

Dual-wavelength Nd:YAP laser at 930 and 1341 nm and sum-frequency mixing for an emission at 549 nm

A dual-wavelength continuous-wave (CW) diode end-pumped Nd³⁺:YAlO₃ (Nd:YAP) laser that generates simultaneous laser action at the wavelengths 930 and 1341 nm is demonstrated. A total output power of 778 mW for the dual-wavelength was achieved at the incident pump power of 17.8 W. Furthermore, intracavity sum-frequency mixing at 930 and 1341 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 103 mW at 549 nm.     

Simultaneous dual-wavelength CW laser operation at 1064 and 930 nm in Nd<Superscript>3+</Superscript>:YAlO<Subscript>3</Subscript>

A dual-wavelength continuous-wave (CW) diode end-pumped Nd³⁺:YAlO₃ (Nd:YAP) laser that generates simultaneous laser action at the wavelengths 1064 and 930 nm is demonstrated. A total output power of 2.15 W (1.57 W at 1064 nm and 0.58 W at 930 nm) for the dual-wavelength was achieved at the incident pump power of 17.8 W with optical conversion efficiency of 12.1%. The M ² values for 930 and 1064 nm lights were found to be around 1.21 and 1.32, respectively.     

LD泵浦Nd:YVO_4双波长运转腔内和频491nm激光器

分析了Nd:YVO4激光器实现双波长运转及腔内和频的条件,利用一种LD泵浦Nd:YVO4晶体产生1 064 nm和914 nm双波长激光束,采用一个线性平凹腔结构,利用腔内Ⅰ类临界相位匹配LBO和频,获得了连续波输出的全固态激光器。实验采用端面结构,在5.0 W的808 nm泵浦功率下,获得了最高功率为2.5 mW连续波TEM00的激光输出,光-光转换效率为0.05%。     

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.     

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.     

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%.     

Tunable dual-wavelength operation of an external cavity semiconductor laser

Tunable dual-wavelength operation of a laser diode has been achieved using a dual-period holographic element. The holographic element was positioned in Littrow configuration in an external cavity. The design of this holographic element was based on the superposition of a constant-period grating and a variable-period grating on the same location in a photoresist. We observed simultaneous emission at two wavelengths from a visible semiconductor laser operated with this holographic element. The spectral separation of the dual-wavelength output was varied from 0.76 to 6.27 nm by a simple translation of the holographic element.     

Simple erbium-doped dual-ring fiber laser configuration for stable and tunable dual-wavelength output

We propose and experimentally investigate a stable and tunable dual-wavelength erbium-doped fiber (EDF) dual-ring laser scheme. Here, two tunable bandpass filters (TBFs) are used inside the dual-ring gain cavity to generate dual-wavelength lasing. And, due to the gain competition of the EDF gain cavity, the mode-spacing (Δλ_s) of lasing dual-wavelength will be limited at different operating wavelengths. Hence, the minimum and maximum mode-spacing in the proposed EDF laser scheme are 0.75 and 15.35 nm in C-band range. Besides, the output performances of proposed fiber laser have also been studied and analyzed.     

First-Stokes Wavelengths at 1175.8 and 1177.1 nm Generated in a Diode End-Pumped Nd:YVO_4/LuVO_4 Raman Laser

A diode end-pumped acousto-optic Q-switched Nd:YVO_4/LuVO_4 Raman laser is demonstrated. Both YVO_4 and LuVO_4 can work as Raman gain, and slightly different active vibration modes of both crystals can result in different first-Stokes wavelengths. The output characteristic as the Raman competition between YVO_4 and LuVO_4 crystals for the laser systems with both shared cavity and coupled cavity is experimentally investigated.For the shared cavity, simultaneous Raman conversion in both YVO_4 and LuVO_4 crystals is achieved with dualwavelength emission at 1175.8 and 1177.1 nm. The maximum output power of 1.03 W and the conversion efficiency of 10.3% are obtained. The 0.84 W single first Stokes wavelength at 1177.1 nm with LuVO_4 Raman conversion is achieved with the coupled cavity. The results show that the coupled cavity with short Raman cavity can obtain a narrow pulse width. The separated laser crystal and Raman gain media with different vanadates in shared cavity have advantages in achieving dual-wavelength lasers with small frequency intervals.     

Tunable single and multiwavelength continuous-wave c-cut Nd:YVO4 laser

We report a discretely tunable, single and multiwavelength continuous-wave diode-end-pumped laser with a c-cut Nd:YVO₄ crystal lasing on the ⁴F_3/2?C⁴I_11/2 intermanifold transitions and an intracavity sub-THz free-spectral-range etalon. Experimental results show that it is tunable in the discrete regions of 1066.5?C1066.8, 1083.1?C1084.6, and 1087.2?C1088.2?nm and operates simultaneously at dual-wavelengths of (1084.6, 1087.4), (1066.5, 1088.0), (1066.8, 1083.3) nm by changing the angle of an intracavity etalon with 0.67 THz free-spectral range. With a proper etalon angle, the laser can also simultaneously oscillate at four wavelengths of 1066.9, 1082.9, 1085.7, and 1088.3?nm with a total output power of 1.2?W at an incident diode pump power of 15?W. Similar performance of the laser at different wavelengths was also achieved by using a 0.88?THz free-spectral-range etalon in the same laser cavity.