共查询到18条相似文献,搜索用时 265 毫秒
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细菌视紫红质(bacteriorhodopsin,简称BR)是嗜盐菌细胞膜内的一种光敏蛋白质。BR薄膜材料具有优异的光循环特性和光致变色特性,可作为信息存储材料。本文讨论了BR所记录图像的对比度与读出光波长变化之间的关系。实验中利用YAG激光器二倍频532nm激光作为图像记录光,白光光源通过单色仪选出单色光作为图像读出光,观察BR膜所记录图像对比度随读出光波长变化趋势,并利用图像灰度积分的方法得到记录图像对比度变化曲线。读出光在470nm-620nm波长范围内,读出为正像;460nm波长附近,图像消失;380nm-450nm波长范围内,图像出现反转。 相似文献
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阐述了利用细菌视紫红质薄膜(BR薄膜)优良的非线性光学特性作为光寻址的空间光调制器的实验研究.BR有两个重要的光敏中间态(B态和M态),其吸收带(B态吸收峰为570nm,M态吸收峰为412nm)重叠区域较少,利用其正向(B→M)和逆向(M→B)光反应之间转化关系和B态与M态的差异吸收实现了相干光学图像到非相干光学图像的转换实验.采用经基因改性的细菌视紫红质薄膜(BRD96N)材料,使用670nm相干光作为写入光,530nm非相干光作为读出光,得到了分辨率约为200 lines/mm,对比度约为2.1∶1的
关键词:
光寻址空间光调制器
细菌视紫红质薄膜(BR薄膜)
非线性光学特性
相干光与非相干光图像相互转换 相似文献
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Osamu Wada 《光学与光电技术》2015,13(1):5-8
首先对未来系统光子器件的关键问题进行了综述。并且对半导体纳米结构,特别是基于量子点材料的超快开关器件取得的最新进展进行了讨论。其中包括基于量子点的半导体光放大器,其在超过40Gb/s的速率下展现出偏振不敏感特性;新型基于量子点的垂直腔结构的光开关,其展现出超快、节能、全光开关的特性。概括和讨论了未来基于纳米结构的光子器件的应用。 相似文献
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研究了一种新型双共轭链有机染料分子的双光子吸收(TPA)及其光功率限幅特性,实验研究了该有机染料的双光子吸收谱和光功率限幅曲线. 结果证实在浓度为1×10-2 mol/L的四氢呋喃(THF)溶液中,该有机染料在近红外区有宽达400nm的宽带非线性双光子吸收及光功率限幅特性. 它的双光子吸收谱存在三个峰,分别位于730,850和980nm,并且在850nm处有最大的TPA截面,为σ′2=25.9×10-47 cm4 sup>·s
关键词:
宽带
双光子吸收
光限幅
双共轭链有机分子 相似文献
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R. Katouf T. Komikado M. Itoh T. Yatagai S. Umegaki 《Photonics and Nanostructures》2005,3(2-3):116-VI
We report fabrication of ultra-fast optical switches operated at a wavelength of 1064 nm using spin-coated one-dimensional polymeric photonic crystals doped with nonlinear-optical dyes. The optical switches are controlled either by an applied electric-field voltage or by a pump light by use of two different optical-configurations. The response time of the electro-optic switch and the all-optical switch are limited by the applied voltage and the laser used, respectively. The polymeric photonic crystals can be easily fabricated with low cost. 相似文献
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高质量三维光子晶体的实验制备及理论分析 总被引:2,自引:0,他引:2
对压强控制自组装法进行了改进,采用了密封硅胶颗粒的强吸水装置,为光子晶体样品的制备提供了一个稳定的温度、湿度和压强环境.将温度、压强分别控制在35 ℃、45 mmHg,利用直径为260 nm的聚苯乙烯胶体球进行了高质量三维光子晶体样品的制备.从理论计算和实验测量等方面对制备的光子晶体样品的结构、质量和性能进行了对比分析,结果表明,利用该实验装置进行光子晶体样品的制备时,可重复性高;制备的光子晶体样品具有较为完美有序的密堆结构,质量较好;在光子晶体样品的Г L方向有深且窄的光子带隙和陡峭的带隙边沿.光子带隙深度为83%,宽度为0.073,带隙边沿陡峭度为8%/nm,这为超快全光开关等先进的光学设备的研究奠定了基础. 相似文献
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High quality photonic crystal heterostructures with a thin titania planar defect layer between its two constitutional photonic crystals were fabricated and their structural and optical properties were analyzed. The results suggest that the thin planar defect layer is beneficial to separate the two constitutional photonic crystals from each other and to reduce the roughness of the interface. The quality of the resulting photonic crystal heterostructures is improved largely and the main features of the photonic band gaps of the two constitutional photonic crystals are inherited. The predominant optical quality of these heterostructures (e.g. deep double photonic band gaps and steep photonic band edges) may afford new flexibility and functionality for engineered photonic behavior in practical devices such as late-model light-operated switches. 相似文献
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半导体光放大器的光-光互作用及其应用 总被引:1,自引:0,他引:1
半导体光放大器(SOA)中的非线性系数约为普通光纤的10^9,为光子晶体光纤的10^7,而且有4种光-光互作用,即交叉增益调制(XGM)、交叉相位调制(XPM)、交叉偏振调制(XSM)及四波混频(FWM),可以灵活地组成各种光信号处理器件,如波长变换器、全光触发器、全光逻辑、全光时钟恢复、全光缓存器……等,正成为整个光信号处理的基础。文章介绍了它们的原理和简单应用。 相似文献
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Polarization Beam Splitter Based on Self-Collimation Effect in Two-Dimensional Photonics Crystal
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A photonic crystal polarization beam splitter based on the self-collimation effect is proposed. By means of the plane wave expansion method and the finite-difference time-domain method, we analyse the splitting mechanism in two alternative ways: performing a band gap structure analysis and simulating the field distribution. The results indicate that two beams of different polarizations can be split with an extinction ratio of nearly 20 dB in a wavelength range of POnm. The splitter may have practical applications in integrated photonic circuits. 相似文献
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介绍了Z箍缩初级实验平台激光触发系统的设计和单路样机验证实验结果.采用12台激光器、24个激光触发主开关来实现24路电流脉冲的精确同步,由Nd:YAG四倍频脉冲激光来触发开关,采用水平分光将一台激光器的激光脉冲等分为两束激光,激光聚焦后分别触发相邻的两路主开关.单路样机验证实验获得的激光脉冲的抖动极差小于等于3 ns.主开关的抖动极差小于等于5 ns,3台激光器之间的抖动极差小于等于3 ns.实验结果表明:在主Marx充电电压小于等于75 kV时,光路管道双隔离气室具有良好的绝缘性和密封性;激光光路系统稳定可靠;能量为100 mJ、脉冲宽度为7 ns的266 nm激光经过分光后,能够满足Z箍缩初级实验平台的设计要求. 相似文献
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In a numerical study, we demonstrate the dynamical tunneling (DT) of two counterpropagating (CP) mutually incoherent beams in a two-dimensional photonic lattice, recorded in a photorefractive (PR) crystal. The beams are launched head-on from the opposite faces of a PR crystal in which an optically induced two-dimensional photonic lattice is established. The DT is caused by the spontaneous symmetry breaking of CP beams, which is induced by the nonlinear interaction between the beams and is mediated by the lattice. To observe DT we found no need to introduce a specific external tilt potential, as is done in the conventional Zener tunneling; the tilting is provided by the repulsive interaction between the beams, which causes ejection of one beam from the launching region of the other. As the beams propagate, they move laterally in real time, causing the leakage of radiation from the first Brillouin zone to the second and higher zones. In the process the beams also tunnel from the first photonic band zone to the higher zones, which by definition is the DT. 相似文献