共查询到19条相似文献,搜索用时 93 毫秒
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高效宽带二次谐波转换在光通信、信号处理和光谱学等很多领域都有重要的应用.通常高效宽带二次谐波转换的研究都集中在几个波长,为了得到可调谐准相位匹配高效宽带二次谐波转换,理论分析了准相位匹配和群速度匹配条件.在此基础上,分别计算了0型和Ⅰ型准相位匹配情况下,温度对5 mol%掺杂氧化镁周期性极化铌酸锂和周期性极化铌酸锂晶体准相位匹配高效宽带二次谐波转换的影响.对于5 mol%掺杂氧化镁周期性极化铌酸锂晶体,在0型和Ⅰ型准相位匹配情况下,分别得到了调谐宽度15 nm和341 nm的可调谐准相位匹配高效宽带二次谐波转换;对于周期性极化铌酸锂晶体,在0型和Ⅰ型准相位匹配情况下,分别得到了调谐宽度44 nm和98 nm的可调谐准相位匹配高效宽带二次谐波转换.拓展了准相位匹配高效宽带二次谐波转换的波长范围. 相似文献
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宽带准连续光纤激光在周期极化铌酸锂中倍频特性的研究 总被引:3,自引:2,他引:1
双包层光纤激光器和非线性光学材料(如周期性极化的铌酸锂晶体,PPLN)相结合,开辟了实用性非线性光学器件的一个新领域。研究了准相位匹配周期性极化反转铌酸锂晶体对宽带准连续光纤激光倍频的温度特性和频谱特性。在理论上,从准相位匹配相位失配关系出发,推导了晶体温度与抽运源中心波长的关系以及温度响应带宽,并和已报道实验结果进行了比较,二者符合得很好。此外,还推导了倍频周期极化铌酸锂晶体对抽运基频光源的响应谱线带宽。在实验上,采用长度20mm,极化周期6.5μm,厚度0.5mm的周期极化铌酸锂晶体光纤激光器准连续宽带输出进行了倍频,获得了在不同控制温度下的倍频光光谱,并对此进行了详细分析。 相似文献
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在周期为14.5μm的周期性极化铌酸锂中,利用d31得到了一阶Ⅰ型EY^ωEY^ω-Ez^2ω(oo-e)准相位匹配蓝光二次谐波。在150C下,由114μJ抽运光,得到了52μJ,0.473μm倍频蓝光,对应于平均最大转换效率45.6%。制备了一阶和三阶周期分别为4.5μm和13.5μm的周期性极化铌酸锂。在EY^ωEY^ω-Ez^2ω(ee-e)准相位匹配0.473μm蓝光倍频中。150C下,分别得到了41.3%和19%的倍频转换效率。oo-e准相位匹配比传统的ee-e准相位匹配有较大的光栅周期,尤其在短波长区域倍频输出应用中,降低了周期性结构制作的困难,其较大的容许带宽在实验中提高了频率转换效率。实验结果表明了在周期性极化铌酸锂中准相位匹配倍频的偏振相关性。 相似文献
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提拉法生长掺有溶质的LiNbO3晶体时,有意识地引入周期性生长层,制备了折射率沿生长方向周期变化的LiNbO3晶体。测量和研究了晶体的双折射率和布喇格衍射。实验结果证实晶体中折射率变化周期与生长层周期相一致。 相似文献
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准相位匹配扇形光栅铌酸锂光波导倍频绿光输出 总被引:2,自引:2,他引:0
采用外加电场极化方式对具有扇形光栅的 0 .5mm厚Z切铌酸锂晶体进行极化反转 ,制成了退火质子交换光波导。极化反转周期为 5 .8μm~ 6 .2 μm ,采用Nd∶YAG激光器输出的 1.0 6 4 μm连续激光为基频光波 ,实现了0 .5 32 μm倍频绿光输出 ,相互作用长度为 4mm ,耦入波导的基频光波功率为 10mW ,获得了 2 0 μW的绿色倍频光输出 ,归一化转换效率为 12 5 % (W·cm2 )。 相似文献
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半导体激光直接倍频的488nm蓝光激光器 总被引:4,自引:0,他引:4
利用波导型准相位匹配周期极化反转铌酸锂(PPLN)晶体直接倍频波长为976 nm的连续半导体激光二极管,在最佳晶体工作温度(28℃)下,获得了波长为488 nm的连续蓝光输出,最大输出功率大于20 mW。所用的晶体尺寸为8 mm×1.4 mm×1 mm,波导截面为4.5μm×3.5μm,极化周期为5.2μm。研究了波导型周期极化反转铌酸锂晶体的倍频效率与温度的关系,与普通的周期极化反转铌酸锂相比,倍频效率与温度关系的敏感度较低。同时,由于晶体可以在室温下工作,简化了加温与温控部件,提高了整机的工作效率。在此实验的基础上,制成了一台小型的全固态488 nm连续蓝光激光器。 相似文献
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An electric-field poling process was established that yielded uniform periodically poled lithium niobate (PPLN) in 0.5 mm
thick lithium niobate substrate. We have fabricated 50 mm long fanned as well as multigrating PPLNs having period variations
from 25 μm to 32 μm. These PPLNs are required for quasi-phase-matched (QPM) optical parametric oscillator (OPO) applications.
We have also configured a bench-top OPO set-up based on these PPLNs. 相似文献
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S. D. Liu J. F. Yang J. L. He B. T. Zhang X. Q. Yang F. Q. Liu H. W. Yang J. L. Xu H. T. Huang 《Laser Physics》2011,21(2):327-330
This paper reported a broadband tuning intracavity optical parametric oscillator (IOPO), based on the multiple grating periodical
poled lithium niobate (PPLN) pumped by a acoustic-optical (AO) Q-switched Nd:YVO4 laser. The widely tunable OPO output signal wavelength range from 1390 to 1605 nm, which was obtained by changing PPLN poling
period from 27.8 to 31.6 μm at a certain temperature of 46°C, while the continuous tuning range was measured from 1475 to
1592 nm with the PPLN poling period of 30 μm by varying the temperature of nonlinear crystal PPLN from 50 to 120°C. The maximum
output power of 0.92 W at 1534 nm with the minimum pulse width of 5.17 ns was generated under the incident pump power of 9.6
W at 808 nm. The corresponding peak power and single pulse energy were calculated to be 5.94 kW and 30.7 μJ, respectively.
The M
2-factor was measured to be 2.01 at the signal power of 0.4 W. 相似文献
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设计并研制了一种基于复合腔结构的波长可调谐、瓦级连续输出的橙红色激光器.该激光器是由半导体激光侧泵Nd∶GdVO_4晶体产生p-偏振1 062.9nm基频光的谐振腔和使用周期性极化晶体MgO∶PPLN(三个极化周期为29.0μm、29.8μm和30.8μm)的单共振光学参量振荡器组成.在两个谐振腔的重叠区域,利用Ⅱ类临界相位匹配KTP晶体对s-偏振信号光与p-偏振1 062.9nm基频光进行腔内和频.通过对MgO∶PPLN晶体进行三个不同极化周期的调谐和30℃~200℃范围内的温度调谐,在三个波段(613.4~619.2nm@29.0μm、620.2~628.9nm@29.8μm和634.4~649.1nm@30.8μm)获得了波长可调谐的橙红色激光连续输出,并在相应波段(3 980.0~3 758.5nm@29.0μm、3 714.2~3 438.3nm@29.8μm和3 278.0~2 940.2nm@30.8μm)获得了波长可调谐的中红外闲频光的连续输出.在30℃最低调谐温度,通过改变晶体的极化周期,在613.4nm、620.2nm和634.4nm处测得最大连续输出功率分别为1.52 W、2.21 W和3.03 W,对应的三束闲频光最大连续输出功率分别为2.36 W@3 980.0nm、3.17 W@3 714.2nm和4.13 W@3 278.0nm. 相似文献
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We demonstrate electro-optic spectral tuning in a continuous-wave periodically poled LiNbO(3) (PPLN) optical parametric oscillator (OPO). We achieve 8.91 cm(-1) of rapid spectral tuning, with a linear tuning rate of 2.89 cm(-1) /(kV/mm), by applying electric fields up to +/-1.5 kV/mm across the crystal while it is operating within the OPO. Intentionally poling the PPLN crystal with an asymmetric domain structure enables tuning, and numerical predictions closely match the experimental observations. The tuning is considerably larger than the typical operational bandwidth of the OPO, indicating that we are in fact shifting the gain curve of the PPLN crystal. 相似文献
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O.?Caballero-Calero A.?García-Caba?es M.?Carrascosa F.?Agulló-López J.?Villarroel M.?Crespillo J.?Olivares 《Applied physics. B, Lasers and optics》2009,95(3):435-439
The generation of periodically poled structures in waveguides prepared by swift-heavy-ion (SHI) irradiation, i.e. in the electronic
stopping power regime, has been achieved following two different strategies. In one of them we have prepared bulk PPLN samples
by an applied electrical field, followed by irradiation with F ions at 22 MeV. After the ion irradiation, a waveguide showing
a high optical confinement is obtained, preserving the original PPLN structure. The second strategy consisted of electric
periodic poling of previously fabricated swift-ion-irradiated waveguides. To our knowledge this method has not been, so far,
successful for conventional implanted waveguides. The successful fabrication of PPLN structures on novel waveguides prepared
by SHI irradiation offers a promising potential for nonlinear integrated optical devices. 相似文献
18.
Widely tunable difference frequency generation around 3.4 μm using index dispersion property of PPLN
In this paper, the wide difference frequency generation (DFG) tuning characteristics around 3.4 μm are investigated by using
the index dispersion property of PPLN. With a ytterbium doped fiber laser (YDFL) and an erbium doped fiber laser (EDFL) as
the fundamental light sources, our simulation results show that the quasi-phase matching (QPM) wavelength acceptance bandwidth
(BW) for the pump is much larger than that for the signal. Although the positions of the broadened QPM pump bands vary with
the poling period and the signal wavelength, the corresponding idler tuning ranges center around 3.4 μm. With a signal wavelength
of 1.57 μm, an idler tuning range of greater than 170 nm is experimentally obtained in the 30 uniform grating PPLN. When the
signal wavelength and the poling period are respectively changed to 1.55 and 29.50 μm, wide DFG tuning operations around 3.4
μm are also achieved with the crystal temperature adjusted to adapt the change. 相似文献
19.
X. -L. Dong W. -Y. Yang B. -G. Sun J. -F. Yang B. -T. Zhang H. -T. Huang S. -D. Liu 《Laser Physics》2010,20(9):1787-1790
A widely continuous tunable eye-safe laser based on periodical poling lithium niobate (PPLN) crystal, driven by a diode-end-pimped
acoustic-optical (AO) Q-switcher Nd:YVO4 laser was demonstrated. Under the pumped power of 7.74 W at 808 nm and the frequency repetition rate of 45 kHz, the maximum
output power of 0.58 W at 1534 nm with the minimum pulse duration of 7.53 ns was obtained. The corresponding peak power and
single pulse energy were calculated to be up to 1.71 kW and 12.9 μJ, respectively. By changing 20 different channels with
poling period between 27.8 to 31.6 μm, we measured widely continuously tunable wavelength coverage from 1390 to 1605 nm. 相似文献