哈尔滨工业大学可调谐(气体)激光技术国家级重点实验室，黑龙江 哈尔滨 150001
2 μm、中波红外(3～5 μm)和长波红外(8～12 μm)波段位于大气传输窗口和人眼安全范围内，涵盖众多气体原子和分子的共振吸收峰，在光谱学、遥感、通信、地球大气环境监测和光电对抗等领域具有重要的应用价值。目前，获取中长波红外波段激光的方法分为线性和非线性两种。首先分析了两种方法在中长波红外激光领域的国内外最新研究进展。之后详细地介绍了哈尔滨工业大学可调谐(气体)激光技术国家级重点实验室在非线性光学频率转换领域近三年取得的研究成果，包含Ho∶YAG调Q激光器及其泵浦的磷锗锌(ZnGeP2, ZGP)、硒镓钡(BaGa4Se7, BGSe)和硒化镉(CdSe)三种非线性晶体在中长波红外非线性光学频率转换器中的应用。相信随着2 μm超短脉冲激光器的发展，高功率超短脉冲中长波红外激光技术会成为未来的研究热点。
哈尔滨工业大学 可调谐激光技术国家级重点实验室，黑龙江 哈尔滨 150001
2 μm、中波红外3~5 μm及长波红外8~12 μm波段的激光处于大气传输窗口，在激光医疗、环境监测、激光雷达、化学遥感和红外对抗等领域有着非常广阔的应用前景。基于非线性频率转换技术，采用非线性光学晶体在实现中长波红外固体激光输出方面具有结构简单、宽调谐和高功率等技术优势。尤其是使用2 μm单掺Ho固体激光器泵浦ZnGeP2晶体，在3~5 μm和8~10 μm中长波红外输出中性能优异。在平均输出功率方面，目前可达到102 W@3~5 μm、12.6 W@8.2 μm以及3.5 W@9.8 μm的输出水平，光束质量M2均小于3，其中中波的光光转换效率可达60%。文中针对2 μm单掺Ho固体激光器及ZnGeP2晶体在中长波输出方面进行了总结。
中长波红外 非线性光学 固体激光器 2 μm 2 μm middle-long-wave infrared nonlinear optics solid laser 红外与激光工程
2020, 49(12): 20201056
哈尔滨工业大学, 可调谐激光技术国家级重点实验室, 哈尔滨 150001
中波红外3~5 μm波段以及长波红外8~12 μm波段的激光处于大气传输窗口, 在激光成像、环境监测、激光雷达、激光医疗、化学遥感和红外对抗等领域有着非常广阔的应用前景。基于非线性光学晶体, 采用光学非线性频率变换技术在实现中长波红外固体激光输出方面具有明显的技术优势。该方法激光器结构简单, 且晶体本身并不参与能量交换, 因而没有量子亏损, 从而产热很少。同时具有单色性好、宽调谐、高功率等优点。本文针对常用以及新型非线性光学晶体, 对其应用于中长波红外固体激光器的研究进展做了详细的总结。
中长波红外激光 固体激光器 非线性光学晶体 光学非线性频率变换技术 mid- and long-wave infrared laser solid-state laser nonlinear optical crystal optical nonlinear frequency conversion technology
Author Affiliations
Abstract
National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150001, China
We demonstrate a single-longitudinal-mode Ho3+:YVO4 unidirectional ring laser based on the acousto-optic effect, utilizing the features of the acousto-optical Q switch and half-wave plate to achieve unidirectional operation. The maximum power achieved in the single-longitudinal-mode at 2053.9 nm is 941 mW when the absorbed power is set as 4.4 W, yielding a nearly 50% slope efficiency. The M2 factor is 1.1. The results show that such a technique offers a potentially promising new method for achieving a high power and narrow linewidth 2 μm single-longitudinal-mode laser.
140.3560 Lasers, ring 140.3570 Lasers, single-mode 140.3580 Lasers, solid-state Chinese Optics Letters
2017, 15(3): 031402
Author Affiliations
Abstract
National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150001, China
In this Letter, we demonstrate a diode-pumped electro-optical cavity-dumped Tm:YAP laser for the first time to our knowledge. A pulse width of 7.1 ns is achieved at a wavelength of 1996.9 nm. A maximum output power of 3.02 W is obtained with a pump power of 58.8 W at a repetition rate of 100 kHz and a high-voltage time of 1000 ns, corresponding to an overall optical-to-optical conversion efficiency of 5.2%. In addition, we study the effect of repetition rate and high-voltage time on the output power characteristics of a cavity-dumped Tm:YAP laser.
140.3460 Lasers 140.3480 Lasers, diode-pumped 140.3580 Lasers, solid-state Chinese Optics Letters
2015, 13(10): 101402
Author Affiliations
Abstract
National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150001, China
A diode-end-pumped tunable twisted-mode cavity Tm, Ho:YAG laser with single-longitudinal-mode (SLM) operation is demonstrated in this Letter. The maximal SLM output power is 106 mW with a slope efficiency of 4.86%. The wavelength can be changed from 2090.38 to 2097.32 nm by tuning the angle of an etalon.
140.3570 Lasers, single-mode 140.3600 Lasers, tunable 140.3480 Lasers, diode-pumped 140.3580 Lasers, solid-state Chinese Optics Letters
2015, 13(11): 111403
Author Affiliations
Abstract
1 Department of Control Engineering, Naval Aeronautical and Astronautical University, Yantai 264001, China
2 Navy Unit 91404, Qinhuangdao 066001, China
3 National Key Laboratory of Tunable Laser Technology, Harbin Institute of Technology, Harbin 150080, China
Broadband mid-infrared (IR) supercontinuum laser is generated in standard single-mode fiber-28 directly pumped by a 2054 nm nanosecond Q-switched Tm,Ho:YVO4 laser. The average output powers of 0.53 W in the ~1.95–2.5 μm spectral band and 0.65 W in the ~1.97–2.45 μm spectral band are achieved at pulse rate frequencies of 7 and 10 kHz, and the corresponding optic-to-optic conversion efficiencies are 34.6% and 42.4% by considering the coupling efficiency. The output spectra have extremely high flatness in the range 2060–2400 and 2060–2360 nm with negligible intensity variation (<2%), respectively. The output pulse shape is not split, and pulse width is reduced from 29 to ~15.4 ns. The beam quality factor M2 is 1.06, measured using traveling knife-edge method, and the laser beam spot is also monitored by an IR vidicon camera.
060.2390 Fiber optics, infrared 060.2430 Fibers, single-mode 060.4370 Nonlinear optics, fibers Chinese Optics Letters
2014, 12(9): 090605
Author Affiliations
Abstract
In this letter, we report a Ho:YVO4 laser pumped by a 1.94-μm laser in both continuous-wave (CW) and Q-switched modes. The output performance of the Ho:YVO4 laser is compared with different output coupler transmissions. By use of the output coupler transmissions of T=30%, we obtain the maximum CW output power of 3.9 W at 2052 nm, with beam quality factor of M2=1.09 for the absorbed pump power of 12.5 W. For the Q-switched mode, we achieve maximum output energy per pulse of 0.38 mJ and the minimum pulse width of 25 ns, corresponding to the peak power of 15.2 kW.
140.3070 Infrared and far-infrared lasers 140.3540 Lasers, Q-switched 140.3580 Lasers, solid-state Chinese Optics Letters
2014, 12(8): 081401
Author Affiliations
Abstract
This letter demonstrates an efficient high-power high-brightness 2-\mu m continuous-wave (CW) laser with double-end, diffusion-bonded Tm, Ho:YVO4 crystal cooled with liquid N2. The reduction in thermal stress in the composite Tm, Ho:YVO4 rod enabled the laser to achieve a laser output power of 23.4 W at 2.05 \mu m, which is 1.37 times higher than that of the non-composite Tm, Ho:YVO4 rod. The corresponding slope efficiency is 37.3% and the optical–optical conversion efficiency is 35.4%. The beam quality M2 factor is about 1.85 at 20 W output level with circularly symmetric beam spot.
140.3480 Lasers, diode-pumped 140.3580 Lasers, solid-state 140.5680 Rare earth and transition metal solid-state lasers Chinese Optics Letters
2013, 11(9): 091404
Author Affiliations
Abstract
We describe a Q-switched Er:GdVO4 laser resonantly pumped by a MgO-doped periodically poled LiNbO3 optical parametric oscillator (MgO: PPLN OPO) at 1 536 nm. In continuous-wave lasing, the maximum output power is 1.14 Wwith an incident pump power of 4.7 Wand a slope efficiency of 27%. In Q-switched operation, 1.1 mJ of output pulse energy is achieved at 200 Hz. The upper-state lifetime at different pulse repetition frequencies is also calculated.
140.3500 Lasers, erbium 140.3540 Lasers, Q-switched 140.3580 Lasers, solid-state Chinese Optics Letters
2013, 11(3): 031405
