共查询到19条相似文献,搜索用时 718 毫秒
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用酞菁酮金属有机染料首次演示了基于反饱和吸收和自聚焦两种效应的光限幅器。实验和理论分析表明,这种限幅器的输入阈值功率由反饱和吸收决定,而自聚焦使限幅器的最大限幅输出功率降低,限幅效果显著增强。 相似文献
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C60/PSt复合材料的反饱和吸收与光限幅特性 总被引:4,自引:1,他引:3
报道了C60/PSt(Polystrene)复合材料的制备,测量了材料的线性吸收光谱,研究了不同线性透射率的C60/PSt材料的反饱和吸收与光限幅特性. 相似文献
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利用纳秒脉冲激光下的z扫描方法对两种新型卟啉衍生物在450 nm—490 nm范围内的反饱和吸收进行了研究.通过与四苯基卟啉的比较发现,在Soret和Q吸收带之间,两种新型卟啉衍生物都具有大的反饱和吸收.采用五能级模型对实验结果进行了分析,比较了在不同波长范围内各个样品的优势.实验结果表明,在450 nm—490 nm范围内,两种新型的卟啉衍生物有着比四苯基卟啉更好的光限制应用前景.
关键词:
反饱和吸收
z扫描')" href="#">z扫描
卟啉衍生物 相似文献
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C60/PMMA复合材料的反饱和吸收与光限幅特性研究 总被引:1,自引:0,他引:1
本文报导C60/PMMA复合材料的制备方法,并采用调QNd:YAG倍频脉冲激光照射C60/PMMA夏合材料,研究了其反饱和吸收与光限幅将性。在线性透射率为46%条件下,光限幅阈值能量密度为65mJ/cm2,材料破坏能量密度阈值为600mJ/cm2.与C60甲苯溶液相比具有一定的优点。 相似文献
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CoherenceTimeMeasurementofPicosecondPulsesUsingReverseSaturableAbsorptioninLeadPhthalocyanineLIFengSONGYinglinYANGKunLUIShuti... 相似文献
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合成了一种新型有机金属配合物Cetyltrimethylammonium-bis(2-thioxo-1,3- dithiole- 4,5-dithiolato)-copper(简称CtCu)材料.采用单光束Z扫描测试技术,在波长为1 053 nm,脉宽为1 ns的条件下研究了该样品的三阶非线性光学性质.研究发现,该材料具有很强的饱和吸收特性,激发态的有效吸收截面为σeff=1.10×10-19 cm2,与基态吸收截面的比值为1∶484.利用非线性透过率实验验证了材料的饱和吸收特性,并对其产生机理进行了分析.实验结果表明,该材料在近红外波段的激光脉冲压缩方面有潜在的应用前景. 相似文献
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Jingzhou Li Saifeng Zhang Hongxing Dong Yunfei Ma Bin Xu Jun Wang Zhiping Cai Zhanghai Chen Long Zhang 《Particle & Particle Systems Characterization》2017,34(1)
Ultrafast saturable absorption (SA) materials that are capable of blocking the optical absorption under strong excitation have extensive applications in photonic devices. This work presents core/shell colloidal quantum dots (CQDs) which have the quantized energy levels, excellent band gap tunability, and possess significant SA performance. When the band gap is close to the pump pulse energy, the CQDs show significant resonant SA response. At the same excitation conditions, the core/shell CQDs dispersions show better SA response than graphene dispersions, and comparable to the recently reported molybdenum disulfide. The carrier dynamics of the SA of the CQDs is analyzed systematically. The research has also found that the two‐photon absorption of the CQDs show nearly cubic power law of the band gap, while the SA performance keeps almost the same in the nonresonant regime. Further, superior passive Q‐switched laser behavior is observed using the CQDs as a saturable absorber. The results directly reveal the physical processes of this basic problem and broaden the applications of CQDs in photonic devices. 相似文献
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《中国物理快报》2017,(9)
We present a comprehensive understanding of the nonlinear absorption characteristics of CdSe-based nanoplatelets(NPLs) synthesized by the solution-phase method and the colloidal atomic layer deposition approach through Z-scan techniques at 532 nm with picosecond pulses. The CdSe NPLs exhibit strong two-photon induced free carrier absorption(effective three-photon absorption) upon the nonresonant excitation, resulting in a remarkable optical limiting behavior with the limiting threshold of approximately 75 GW/cm~2. A nonlinear optical switching from saturable absorption(SA) to reverse saturable absorption(RSA) with increasing the laser intensity is observed when coating CdSe NPLs with a monolayer of CdS shell to realize the resonant absorption. The SA behavior originates from the ground state bleaching and the RSA behavior is attributed to the free carrier absorption.These findings explicitly demonstrate the potential applications of CdSe-based NPLs in nonlinear optoelectronics such as optical limiting devices, optical pulse compressors and optical switching devices. 相似文献
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Misha Hari S. Mathew B. Nithyaja Santhi Ani Joseph V. P. N. Nampoori P. Radhakrishnan 《Optical and Quantum Electronics》2012,43(1-5):49-58
Silver nano-colloid was prepared by chemical reduction method and its nonlinear absorption properties were investigated by using open aperture z-scan experiment with nanosecond laser pulses operating at 532?nm. Interestingly, a switch over from saturable absorption to reverse saturable absorption was observed when the input intensity is increased from 28.1 to 175.8?MW/cm2. The underlying mechanism responsible for the observed switching behaviour is the interplay between ground state plasmon band bleaching and excited state absorption. Theoretical fitting was done by using a model in which nonlinear absorption coefficient as well as saturation intensity are incorporated. 相似文献
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Saturable Absorption Enchantment of Au Nanorods Based on Energy Transfer between Longitudinal and Transverse Energy Levels 下载免费PDF全文
Four kinds of Au nanorods(NRs)with different aspect ratios are designed to adjust the relationship between resonance energy level of longitudinal(L)and transverse(T)modes.During the femto-second Z-scan experiments,huge saturable absorption phenomena are observed while the energy level T is located between one to two times of the energylevel L.This means that the energy may transfer between longitudinal and transverse energylevels in the same and/or different Au NRs.It effectively depresses the production of revised saturated absorption and increases the saturable absorption efficiency.This method is significant for the preparation of high-efficiency saturable absorption devices. 相似文献
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Suilian Luo Yao Chen Guanghua Fan Fengqiang Sun Shiliang Qu 《Applied Physics A: Materials Science & Processing》2014,117(2):891-894
Micro/nanostructured silver particles with different shapes (flower, wire, and rod) have been prepared and characterized. All the open aperture z-scan curves of silver microrods and silver nanoflowers present a typical reverse saturable absorption. With the increase of incident intensity, the nonlinear absorption coefficients and the third-order optical susceptibilities ImX(3) of nanoflowers increase, but those of silver microrods decrease. Moreover, the silver nanowires show the conversion from saturable absorption to reverse saturable absorption. There was no definite correlation between incident intensity and nonlinear absorption coefficient (β) under the conditions studied herein. And nonlinear optical properties of micro/nanostructured silver particles are dependent on the particle shape in suspensions at 800 nm. 相似文献
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Tsuyoshi Tsujioka Toshio Harada Minoru Kume Kazuhiko Kuroki Masahiro Irie 《Optical Review》1995,2(4):225-228
The possibility of a super-resolution optical memory using a saturable absorption dye mask layer is theoretically discussed. An equation which estimates the transmittance change of the mask layer has been derived. The numerical simulation shows that an efficient super-resolution is performed when the initial optical density of the mask layer is high. 相似文献