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非线性介质光波导中的传输功率和光学双稳态 总被引:1,自引:0,他引:1
本文对结构为非线性包层/线性芯层/非线性衬底的非线性介质光波导的传输特性进行了深入的分析,给出了模场分布函数,色散关系和传输功率的一组形式统一的公式,并对其传输功率的光学双稳态特性进行了讨论. 相似文献
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介电体超晶格是一种新型的有序微结构材料.它具有通常均质材料所不具有的独特优异性能,展现出重要的应用前景.文章介绍了南京大学研究组关于介电体超晶格研究所取得的进展,如将多个光参量过程集成于一块介电体超晶格之中获得了多波长激光同时输出,研制成超晶格全固态三基色激光器原型,在介电体超晶格中将拉曼散射强度增强到104-105倍,用超晶格研制的器件填补了体波超声器件从几百MHz到几千MHz的空白频段,发现了微波与超晶格振动的强烈耦合以及极化激元(polariton)的激发与传播等. 相似文献
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非线性光纤环:2.掺铒光纤全纤光学双稳态实验 总被引:2,自引:2,他引:0
利用掺饵光纤和光纤定向耦合器组成全光纤谐振腔,在光学非线性条件下,实现了全纤光学双稳运转,实验双稳阈值与理论相符。 相似文献
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非线性光纤环:1.光纤双稳态 总被引:2,自引:2,他引:0
利用传输矩阵统一处理各种光纤环谐振腔的线性和非线性特性,发现各种纤环谐振腔在非线性条件均可产生光学双稳现象,对各种非线性纤环双稳特性进行了计算,分析和比较,确定了器件设计原则。 相似文献
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本文首次研究了ZnSe-ZnTe多量子阱在室温下的反射型皮秒激子光双稳,实验结果表明,ZnSe-ZnTe多量子阱在室温下的反射型皮秒光双稳的阈值光强和对比度分别为1.1MW/cm2和6:1.根据测量得到的ZnSe-ZnTe多量子阱在室温下的激子吸收光谱及激子的非线性吸收理论,归结ZnSe-ZnTe多量子阱室温下的皮秒光双稳的主要非线性机理为ZnSe-ZnTe多量子阱的激子饱和吸收引起的折射率变化. 相似文献
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It is shown that the local field in metal spherical particles with a dielectric core in an external varying electric field has two maxima at two different frequencies. The second maximum becomes more important with an increment in the metal fraction. Due to the nonlinear dielectric function of the core, the composite of these inclusions may have two optically induced bistability domains at different frequencies. At rather high metal fraction, two bistability domains merge and form one entire bistability domain. The parameters of these domains are studied numerically. The paper focuses on the second bistability domain, which has not been discussed in the literature so far. This domain exists in a comparatively narrow frequency range and its onset fields are lower than those of the first bistability domain. The lowest bistability onset fields are obtained in the entire domain. This peculiarity of the optical induced bistability in the metal composite with small dielectric cores can be attractive for possible applications. 相似文献
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Govind P Agrawal 《Pramana》1984,22(3-4):293-301
The role of level degeneracy in resonant nonlinear phenomena is examined by considering theJ=1 →J=0 atomic transition. The atomic medium is modelled as a homogeneously broadened three-level system and a closed-form expression
for the medium susceptibility is obtained. It is used to discuss several nonlinear phenomena such as saturated absorption,
optical bistability, and phase conjugation. The two-photon-induced coupling of the ground-state Zeeman sublevels leads to
interesting polarization effects. 相似文献
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研制了室温CdxZn1-xTe/ZNTe多量子阱法布里-珀罗腔光双稳器件,并在该器件上观察到皮秒一级的室温激子光双稳。研究结果表明,CdZn1-xTe/ZnTe多量子阱光双稳器件的光双稳值和对比度分别为363kW/cm^2和4:1。根据CfxZn1-xTe/ZnTe多量子阱的吸收谱和激子非线性理论,归结了CdxZn1-xTe/ZnTe多量子阱光双稳的主要非线性机理为激子的饱和和吸收。 相似文献
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Low-threshold bistable reflection assisted by oscillating wave interaction with Kerr nonlinear medium 下载免费PDF全文
Yingcong Zhang 《中国物理 B》2021,30(8):84203-084203
Owing to the enormously enhanced oscillating wave, a minute variation of the incident light intensity will give rise to a change in the dielectric constant of the Kerr nonlinear medium and lead to a bistable reflection with an ultra-low threshold intensity, which is closely related to the angle of incidence and the thickness of the Kerr nonlinear medium. The criterion for the existence of optical bistability is derived. Our bistability scheme is simple and not limited to the TM-polarization. 相似文献
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为了提高二次谐波产生转换效率,本文提出将一维周期光学超晶格两端贴上未被极化的厚度可以改变的非线性介质层,通过调整附加介质层的厚度来调制基频波的场,从而观察二次谐波产生转换效率的变化情况.结果表明:基频渡场可以很大程度地调制二次谐波产生;随着能量的增加,二次谐波产生转换效率增加,随着能量的减小,二次谐波产生转换效率减小;... 相似文献
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The transmission spectra of two-period metal-dielectric structure are studied through the transfer matrix method. When the dielectric is nonlinear material, an optical bistability has been found. The upper threshold value is insensitive to incident frequency, while the lower threshold value increases with the incident frequency decreasing. The effect of loss from the metal layers on the optical bistability is also considered. 相似文献
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对单层、双层非线性光学薄膜的输出特性进行数值计算,发现材料非线性特性对光学双稳态输出特性影响较大,而选择合适的双层结构可以获得较低的双稳态阈值光强以及光放大作用。双层非线性光学薄膜间的距离以及入射光的准直性极大地影响着双稳态输出特性. 相似文献
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Nonlinear optical transmission through periodically nanostructured metal films (surface-plasmon polaritonic crystals) has been studied. The surface polaritonic crystals have been coated with a nonlinear polymer. The optical transmission of such nanostructures has been shown to depend on the control-light illumination conditions. The resonant transmission exhibits bistable behavior with the control-light intensity. The bistability is different at different resonant signal wavelengths and for different wavelengths of the control light. The effect is explained by the strong sensitivity of the surface-plasmon mode resonances at the signal wavelength to the surrounding dielectric environment and the electromagnetic field enhancement due to plasmonic excitations at the controlled light wavelengths. 相似文献
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利用LB薄膜技术在一定尺寸的钾离子交换玻璃波导上制备了30层四—4—(2、4—二特戊基苯氧基)酞菁铜(简称tapCuPc)Z型LB薄膜,形成覆盖有LB薄膜的四层介质波导.首次报道在室温下采用不同激光脉冲观察覆盖有LB薄膜的光波导片上的光学双稳特性,除去LB薄膜覆盖层后没有观察到光双稳特征. 相似文献
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The discovery and investigation of optically nonlinear behavior of CdS is reviewed. The development is described from nonlinear anti-Stokes excitation via the characterization of inelastic light scattering processes and the identification of high-density phenomena like biexciton creation, excitonic collisions, and electron-hole plasma generation towards very recent time-resolved gain, light-induced grating, and in particular optical bistability experiments. CdS is thus shown to allow for an extremely wide variety of different optically nonlinear processes and may be regarded as a model material for this field. Possible applications show up for several of the described phenomena. 相似文献
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A scheme for switching of the optical bistability (OB) and multi-stability (OM) in a dielectric slab doped with a three-level ladder-configuration n-doped semiconductor quantum well is simulated. It is shown that the bistable behavior of the system in dielectric slab can be controlled via amplitude or relative phase of applied fields. This optical system may provide some new possibilities for test the switching process. 相似文献