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31.
Intrinsic Bistability and Critical Slowing in Tm^3+/Yb^3+ Codoped Laser Crystal with the Photon Avalanche Mechanism
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We present theoretically a novel intrinsic optical bistability (IOB) in the Tm^3+ /Yb^3+ codoped system with a photon avalanche mechanism. Numerical simulations based on the rate equation model demonstrate distinct 10B hysteresis and critical slowing dynamics around the avalanche thresholds. Such an 10B characteristic in Tm^3+ /Yb^3+ eodoped crystal has potential applications in solid-state bistable optical displays and luminescence switchers in visible-infrared spectra. 相似文献
32.
A Continuous-Wave Ho:YA103 Laser with Output 8.5 W Pumped by a 1.91μm Laser at Room Temperature
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A cw high efficient Ho:YAI03 laser pumped by 1.91 μm diode-pumped Tm:YLF laser at room temperature is realized. The maximum output power reaches 8.5 W when the incident pump power is 15.6 W. The slope efficiency is 63.7%, and the Tm:YLF to Ho:YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2 -1.39 measured by the traveling knife-edge method. 相似文献
33.
Widely Tunable Middle Infrared Optical Parametric Oscillator Pumped by the Q-Switched Ho:GdVO_4 Laser
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We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho:GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.05 W, corresponding to a slope efficiency of 74.6%. The ZGP-OPO laser produces 4.2 ns mid-infrared pulses at a pulse repetition rate of 5 kHz. In addition, we obtain 0.8 um of tunable range for the signal wave and 2.1 um of tunable range for the idler wave. 相似文献
34.
We demonstrate the continuous wave p-polarized single longitudinal mode (SLM) operation of an Er:YAG laser at 1617.6nm pumped by a diode-laser with three inserted Fabry-Perot (FP) etalons at room temperature. The Brewster angle inserted FP is applied to obtain the p-polarized laser. For free running, the maximum output power is 570 m W with a pump power of 12.5 W. An incident pump power of 12.5 W is used to generate the maximum p-polarized single longitudinal mode output power of 78.5 m W, corresponding to a slope efficiency of 1.6% and an optical-to-optical efficiency of 0.61%. The beam quality M2 is measured to be 1.15 at the highest SLM output power. This stable polarized SLM oscillation is encouraging due to its application for an injection-locked system used as a master laser. 相似文献
35.
报道了一台二极管泵浦种子注入Tm,Ho:YAP激光器。在重复频率100 Hz时,获得了单脉冲能量2.8 mJ、脉冲宽度289 ns的2.13 m单频脉冲激光输出。利用该种子注入Tm,Ho:YAP激光器作为发射光源,以一个最大标称线速度20.4 m/s、直径10 cm的风扇作为模拟探测目标,通过外差式相干探测的方法进行了激光多普勒测速实验。利用本振光与信号光的激光拍频信号,得到包含模拟探测目标速度信息的多普勒频移,通过数据处理计算出了风扇不同转速条件下模拟探测目标的速度,并与模拟目标的实际速度进行了比对,测量速度误差小于1 m/s。 相似文献
36.
We report the demonstration of passively continuous-wave mode-locking(CWML) of diode-pumped Tm,Ho:YV04 laser using an InGaAs/GaAs multiple quantum-well(MQW) structure semiconductor as the saturable absorber.Stable mode-locking pulses at the central wavelength of 2 041 nm are obtained. The maximum output power is 151 mW.The pulse duration is 10.5 ps at the repetition rate of 64.3 MHz. 相似文献
37.
Comparative investigation of long-wave infrared generation based on ZnGeP2 and CdSe optical parametric oscillators
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Long-wave infrared(IR) generation based on type-II(o→e+o) phase matching ZnGeP 2(ZGP) and CdSe optical parametric oscillators(OPOs) pumped by a 2.05 μm Tm,Ho:GdVO 4 laser is reported.The comparisons of the birefringent walk-off effect and the oscillation threshold between ZGP and CdSe OPOs are performed theoretically and experimentally.For the ZGP OPO,up to 419 mW output at 8.04 μm is obtained at the 8 kHz pump pulse repetition frequency(PRF) with a slope efficiency of 7.6%.This ZGP OPO can be continuously tuned from 7.8 to 8.5 μm.For the CdSe OPO,we demonstrate a 64 mW output at 8.9 μm with a single crystal 28 mm in length. 相似文献
38.
1)经临床及病理诊断的136例官颈鳞癌;24例官颈炎;8例正常官颈鳞状上皮,取自三个不同地区——新疆,北京和湖北。从以上标本提取DNA供核酸杂交用。以32~P-dTTP进行标记的HPV-6B,11,16,18的质粒DNA作为探针,与上述宫颈癌,宫颈炎及正常宫颈上皮DNA进行斑点核酸杂交。部分进行Southern blot杂交和双向电泳。结果表明136例癌中76例的DNA中可检测到HPV-16 DNA的相关序列(56%),並有明显的地区差异——新疆的阳性率为82%(19/23),北京65.3%(32/49),湖北39%(25/64),八例正常宫颈均为阴性。Southern blot杂交及双向电泳表明病毒DNA整合入癌细胞基因之 相似文献
39.
根据激光二极管纵向抽运Tm,Ho:YLF激光器的能级跃迁和能量传递过程,在考虑能量传递上转换(ETU)的情况下,建立了Tm,Ho:YLF主动调Q激光器的准三能级速率方程,得出了激光单脉冲能量的解析表达式.在理论上指出,能量传递上转换不但减小了输出单脉冲能量,而且严重减小了激光上能级寿命.实验上给出了在固定抽运功率下,单脉冲能量随重复频率的变化关系,验证了理论所指出的能量传递上转换减小了激光上能级寿命.
关键词:
二极管抽运
Tm
Ho:YLF晶体
能量传递上转换
速率方程 相似文献
40.