共查询到18条相似文献,搜索用时 127 毫秒
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《中国光学与应用光学文摘》2006,(4)
O437 2006043105含负折射率介质非线性Bragg腔的双稳态特性=Bistableproperties of nanlinear Bragg cavity containing negative re-fractive index materials[刊,中]/蒋美萍(南京理工大学材料科学与工程系.江苏,南京(210094)) ,陈光…∥光子学报.—2006 ,35(4) .—535-539研究了含负折射率介质一维光子晶体非线性Bragg腔的透射特性、光学增强和双稳态特性、对负折射率介质无色散和有色散非线性Bragg腔及由两种正折射率介质构成的非线性Bragg腔的透射谱、光学增强、缺陷模的线宽、入射光的红移量、双稳态开关阈值进行了比较。含负折射率… 相似文献
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非线性Bragg微腔的双稳态研究 总被引:2,自引:0,他引:2
研究了一维Bragg微腔中的光学增强效应,并对F-P腔中Kerr介质的双稳态特性进行了理论分析,并得到相应的数学表达式.研究表明,对聚焦型Kerr介质(χ(3)>0),要产生双稳态特性必须给入射光波预置一定的红移量,若是散焦型介质(χ(3)<0)则要预置一定的蓝移量.红移量(或蓝移量)的临界值与光子晶体的介质折射率、周期数、F-P腔长度、缺陷模的线宽(FWHM)等因素密切相关,它随介质折射率比、周期数、F-P腔长的增大而减小,随缺陷模的线形变窄而降低.要有效地降低非线性介质的双稳态开关阈值,除了尽可能选择较小的合适红移(或蓝移)量外,还要选择|χ(3)|较大的Kerr介质以增强腔内的非线性光学效应. 相似文献
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介质层厚对含负折射率介质Bragg微腔的影响 总被引:1,自引:0,他引:1
研究了介质层厚对含负折射率介质一维光子晶体Bragg微腔的缺陷模和双稳态的影响.在中心频率附近将传输矩阵各矩阵元采用泰勒级数展开并取一级近似,得到了缺陷模频率与介质层厚的关系式及品质因子公式.研究结果表明:一级近似法能很好地解释中心频率附近介质层厚对缺陷模频率的影响.理想Bragg微腔结构的缺陷模品质因子最大;递增正折射率介质层厚和增大缺陷层介质层厚、递减负折射率介质层厚及同时等量递减正和负折射率介质层厚,均可使缺陷模红移,双稳态阈值降低. 相似文献
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本文提出一种只在一层高折射率介质层中掺杂Kerr介质的一维耦合腔光波导.利用一维传输矩阵理论和非线性传输矩阵方法研究了此结构的光学双稳态.根据一维传输矩阵理论分析了此结构的线性特性,包括低频带边模的偏移及场分布的特点,讨论了此结构实现双稳态的原理.研究发现:由于缺陷层中场分布与入射光方向密切相关,而缺陷层光场的局域,将激发Kerr介质的三阶非线性效应,从而改变了缺陷层的折射率,所以不同方向的入射光具有不同的双稳态阈值.利用非线性传输矩阵方法研究了光学双稳态特性.结果表明:由于缺陷层的位置导致缺陷模正方向(由左到右)入射的场分布大于反方向(由右到左)入射的场分布,正方向的阈值低于反方向的阈值,相差一倍. 相似文献
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《中国光学与应用光学文摘》2006,(6)
O437 2006065109腔模红移对非线性微腔双稳态阈值的影响=Effects of red shifting in cavity-mode on the bistable threshold of nonlin- ear microcavity[刊.中]/沈小明(江苏工业学院信息科学系.江苏,常州(213013)),蒋美萍…//量子电子学报.—2006.23(3).——413-415影响非线性微腔双稳态阈值的因素很多,例如电介质折射率、周期数、缺陷层厚度、谱线宽度等,但是腔模红移起到了十分重要的作用。从理论上分析了红移对双稳态阈值的影响。并作了数值模拟。图2参14(于晓光) 相似文献
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含色散与非线性媒质的光子晶体的简正耦合模 总被引:7,自引:3,他引:4
利用传输矩阵方法及对色散媒质采用洛伦兹振子模型,研究了一维含色散媒质的光子晶体的简正耦合模,并计算了该结构的复有效折射率。在光学双稳态中,与仅含非线性媒质的光子晶体相比,得到了低得多的阈值入射光强。 相似文献
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Transmission properties of one-dimensional photonic crystal with two nonlinear defects were investigated based on the nonlinear transfer matrix method. From the inspection of the optical bistabilities around different defect modes, it was found that the threshold of bistability for the bonding mode is always lower than that for the anti-bonding mode. When intensity of the incident wave increases bistability could happen at any wavelength larger than the resonance wavelength of the linear anti-bonding mode in the gap. The threshold of bistability increases initially with the wavelength, then decreases sharply in reaching the resonance wavelength of the linear bonding mode. The coupling behavior of the two defects was also discussed, and it was found that the threshold of bistability increases with the distance between the two defects. A flat spectrum similar to that formed in the photonic crystal molecules was obtained under certain incident intensity. 相似文献
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《Current Applied Physics》2015,15(9):987-992
In this paper, we numerically investigate nonlinear optical responses in dielectric gratings coated by flat metallic surface, where the structural parameters are chosen for wavelengths of operation at the telecom regime. The presented designs show the output light reflection with respect to the incident intensity of increasing, decreasing, and non-monotonic belt-shape functions. Nonlinear optical responses including switching and bistability appeared in the telecom region owing to assistance of surface plasmon resonance excited at the metal/dielectric interface, which enhances the diffraction efficiency and induces the momentum matching for the leaky modes of the dielectric grating. This results in electric intensity-effective refractive index dependence enhancement in the Kerr nonlinear media. Our design and investigation of the linear and nonlinear optical responses will provide a general guideline for a hybrid metallic-dielectric structure-based optical switching/bistability device design. 相似文献
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非线性一维光子晶体波导光双稳 总被引:2,自引:2,他引:0
利用非线性折射率系数较大且非线性时间响应较快的CdSxSe1-x玻璃为材料,设计并制备了非线性一维光子晶体波导光双稳器件,该器件的折射率空间分布呈正弦形式。实验测得双稳开关的阈值功率密度为1.60×105W/cm2,开关时间为63ps。采用时域有限差分方法讨论了光子晶体带隙随入射光强变化而移动的情况,随着入射光功率密度的增加,光子晶体的带隙中心向短波方向移动。同时计算了该器件的双稳特性,理论计算得到双稳开关的阈值功率密度为1.40×105W/cm2,开关时间约为50ps。获得了理论与实验基本一致的结果。 相似文献
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Jian-Feng Tian 《Optik》2011,122(15):1381-1383
Based on the nonlinear coupled mode theory, by using the reversely recursive transmission matrix method, the switching characteristics of linearly chirped nonlinear Bragg gratings (LC-NLBG) have been investigated numerically. The results show that, introducing spatial chirp in fiber gratings is helpful to widen the bistable wavelength range, and the influence of the chirp on the switching-on threshold and the on-off ratio of the bistable switching are obvious, the chirp-dependent bistability is due to the difference of the axial distribution of forward wave intensity in the gratings. 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