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71.
量子纠缠是量子信息领域的核心资源,目前利用β型硼酸钡(BBO)晶体参量下转换制备的纠缠光子对的亮度较低,它直接制约了量子通信的最远距离,已无法满足星地实用化量子通信的发展需求.利用周期极化KTiOPO4晶体,采用准相位匹配技术设计产生了一种后选择的纠缠源,测得的符合计数达到了16×103s-1 mW-1,极化对比度达到27∶1,在亮度上比基于BBO的量子纠缠光源提高了一个数量级以上.这一高亮度的纠缠源可以广泛应用于量子密钥分发、量子隐形传态以及量子计算等新兴量子信息领域,为实现全球化量子通信提供了有力的保障.
关键词:
纠缠态
准相位匹配
4晶体')" href="#">周期极化KTiOPO4晶体 相似文献
72.
研究了基于周期极化反转铌酸锂光波导级联二阶非线性效应实现非归零码到归零码高速全光码型转换的新方案,使用的是马赫-曾德尔干涉仪结构.转换原理是非归零码信号光在级联倍频和差频过程中受到的放大作用引起马赫-曾德尔干涉仪的不平衡,进而通过干涉相消产生归零码信号光输出.首先从耦合波方程出发,数值模拟了非归零码到归零码码型转换过程.然后分析了波导长度、光功率、相对时延对消光比的影响并对码型转换进行了优化设计.最后分析了转换带宽,模拟计算表明信号光在90nm的3dB带宽内可调谐,进而可以实现多信道的同时转换.
关键词:
码型转换
级联倍频和差频
周期极化反转铌酸锂
马赫-曾德尔干涉仪 相似文献
73.
1-W, high-repetition-rate room temperature operation of mid-infrared optical parametric oscillator based on periodically poled MgO-doped LiNbO 下载免费PDF全文
In this paper a high-repetition-rate mid-infrared (mid-IR) optical parametric oscillator based on periodically poled MgO-doped LiNbO3 (PPMgLN) at room temperature was demonstrated. The maximum average mid-IR output power at 3.63μm was 1.02 W with the repetition rate of 60kHz and corresponding efficiency from the pump to the idler was 26.7%. The temperature tuning and the period tuning characteristics were also discussed. 相似文献
74.
Compact efficient optical parametric generator internal to a Q-switched Nd:YVO4 laser with periodically poled MgO:LiNbO3 下载免费PDF全文
This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVOquasi-phase-matching,
intracavity optical parametric generator, periodically poled
MgO-doped lithium niobate (PPMgLN) Project supported by the National
Natural Science Foundation of China (Grant Nos 10474071 and
60671036). 4265K, 4260F, 4270 This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVOquasi-phase-matching,
intracavity optical parametric generator, periodically poled
MgO-doped lithium niobate (PPMgLN) Project supported by the National
Natural Science Foundation of China (Grant Nos 10474071 and
60671036). 4265K, 4260F, 4270 This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVOquasi-phase-matching,
intracavity optical parametric generator, periodically poled
MgO-doped lithium niobate (PPMgLN) Project supported by the National
Natural Science Foundation of China (Grant Nos 10474071 and
60671036). 4265K, 4260F, 4270 This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVOquasi-phase-matching,
intracavity optical parametric generator, periodically poled
MgO-doped lithium niobate (PPMgLN) Project supported by the National
Natural Science Foundation of China (Grant Nos 10474071 and
60671036). 4265K, 4260F, 4270 This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVOquasi-phase-matching,
intracavity optical parametric generator, periodically poled
MgO-doped lithium niobate (PPMgLN) Project supported by the National
Natural Science Foundation of China (Grant Nos 10474071 and
60671036). 4265K, 4260F, 4270 This paper demonstrates a compact efficient optical parametric
generator internal to a Q-switched diode-end-pumped Nd:YVO$_{4}$
laser with periodically poled MgO:LiNbO3(PPMgLN). With the
Q-switch set at a repetition rate of 25kHz and the PPMgLN crystal
operated at room temperature (25\du\,), the intracavity optical
parametric generator threshold was reached as a diode pump power of
0.9\,W. A maximum signal output power of 0.34W with a pulse width
of 25\,ns and a beam quality factor of 1.4 was obtained at an
incident diode power of 3.4\,W, leading to a conversion efficiency of
10{\%} with a slope efficiency of 14.4{\%}. By varying the crystal
temperature from 25 to 200\du, the output signal wavelengths were
tuned in range of 1506--1565\,nm. Over a 30-minutes interval, the
instability of the signal power was measured to be less than 1{\%}.
In addition, the threshold pump intensity for the intracavity optical
parametric generator is theoretically investigated, and the obtained
result is in good agreement with the experimental results. 相似文献
75.
76.
77.
78.
在光纤环形腔激光器中引入周期极化反转铌酸锂(PPLN)光波导,用该激光器产生的连续光作为抽运光和控制光,使其与外加的信号光发生非线性效应实现可调谐波长转换.介绍了基于准相位匹配的PPLN光波导中的和频与差频级联型全光波长转换器的基本原理.对抽运光、信号光、控制光以及转换光的光功率随着PPLN光波导的变化进行了模拟.还对转换效率随着转换光波长的变化进行了数值计算.实验验证了该波长转换器的可调谐性.
关键词:
周期极化反转铌酸锂
和频与差频
可调谐全光波长转换
光纤环形腔激光器 相似文献
79.
I. I. Argatov 《Mathematical Notes》2005,77(1-2):15-25
We consider the Dirichlet problem for the Laplace operator in the exterior of a narrow infinite cylinder with periodically varying directrix. The solution is sought in the class of functions logarithmically increasing as the distance from the cylinder is increased. The reduced logarithmic capacity is defined as a generalization of the logarithmic capacity (of the outer conformal radius).We construct and justify the asymptotics of the solution of the problem as the ratio of the diameter of the cross-section of the cylinder to its period tends to zero.Translated from Matematicheskie Zametki, vol. 77, no. 1, 2005, pp. 16–27.Original Russian Text Copyright © 2005 by I. I. Argatov.This revised version was published online in April 2005 with a corrected issue number. 相似文献
80.
A diode-pumped actively Q-switched Nd:GdVO4 green laser with periodically poled KTP (PPKTP) and Acoustic-optic (AO) modulator has been realized. The dependences of pulse energy, pulse width, and peak power on incident pump power are measured. At the pump power of 4.1 W and repetition rate of 10 kHZ, we can obtain a 19.2 ns pulse with pulse energy of 0.11 mJ and peak power of 5.8 kW, which are almost three times of that in the conventional KTP green laser, respectively. A rate equation model is introduced to theoretically analyze the results obtained in the experiment, in which the Gaussian spatial distribution of the intracavity photon density is taken into account. The numerical solutions of the rate equations agree with the experimental results. 相似文献