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11.
《印度化学会志》2023,100(3):100928
A new azo β-diketone (NA1) compound is synthesized by coupling reaction of 4-aminoantipyrine with acetylacetone. The NA1 compound is characterized via FTIR, Mass, 1H NMR and 13C NMR spectroscopies. The keto-enol tautomers of the compound electronic structures and energies are investigated using density functional theory (DFT) via B3LYP method/6-311G (d,p) level. The NA1 compound nonlinear optical (NLO) properties are studied via the diffraction patterns (DPs) and the Z-scan where the compound nonlinear index of refraction (NIR), the optical limiting (OLg) property using 473 nm visible, low power, continuous (cw) laser beam are used while the all-optical switching (AOS) property is studied using two laser beams of wavelengths 473 nm and 532 nm. 相似文献
12.
采用射频磁控反应溅射技术制备了a-Si/SiN_x超晶格材料,并采用热退火技术对材料进行处理。利用吸收光谱和X射线衍射谱对材料进行表征,结果表明Si层呈现非晶态。为研究材料的三阶非线性光学特性,对材料进行Z扫描研究,测量数据表明,材料的非线性吸收为反饱和吸收,材料非线性折射率呈现为负值,该材料的χ(3)的实部为4.57×10~(-17)C(1.39×10~(-7)esu),虚部为1.49×10~(-17)C(4.48×10~(-8)esu),该极化率数值比体硅材料的χ(3)值大5个数量级。对该材料非线性光学产生的机理进行了研究,认为材料体现出的较强的量子限制效应是非线性极化率增强的主要来源。 相似文献
13.
Lei Tian Pengfei Shi Jieying Wu Yufang Zhou Minghua Jiang 《Journal of luminescence》2007,127(2):423-430
The title compounds, several Schiff bases with D-π-D type have been successfully synthesized from reaction of 4-(N-dialkylamino) benzaldehyde and hydrazine or p-phenylenediamine in ethanol. These compounds were characterized by IR, 1H NMR, elemental analysis and electronspray mass spectrometry. One-photon fluorescence and two-photon fluorescence properties have been investigated. The two-photon absorption (TPA) cross section (σ) of these compounds was obtained by using the open-aperture Z-scan technique. Based on theoretical calculations and factual test, the influence that a series of substituted groups and the conjugated frame imposed on TPA cross section were systematically discussed. 相似文献
14.
介绍了由Sheik-Bahae等人提出的、用于测量材料三阶非线性的单光束Z-scan技术。该技术能同时测量材料的非线性折射和非线性吸收,并能给出非线性折射的符号。介绍了以该技术为基础并经改进的几种测量技术:遮挡Z-scan,I-scan和微分Z-scan。引出了近10年来新发展的相位4f相干成像技术,并对其基本原理进行了阐述,分析了其应用特点。该技术具有使用单脉冲进行测量,光路简单,测量灵敏度高,无样品移动等特点。 相似文献
15.
Umakanta Tripathy R. Justin Rajesh Prem B. Bisht A. Subrahamanyam 《Journal of Chemical Sciences》2002,114(6):557-564
The excited state absorption cross-section of 5,5′-dichloro-11-diphenyl-amino-3,3′-diethyl-10, 12-ethylinethiatricarbocyanine
perchlorate (IR140) have been measured by using a single beam transmission technique. Z-scan experiments have been used to find out a few nonlinear
parameters. The excited state relaxation times have also been measured by using laser induced transient grating (LITG) technique. 相似文献
16.
The nonlinear optical properties of the poly1,4-diazophenylene-bridged-tris(8-hydroxy-quinoline) aluminum (PDPAlq3) solution were studied using single beam Z-scan technique with a continuous-wave Diode laser radiation at 657.2 nm with 10 Hz repetition rate. The results show that the solution of PDPAlq3 exhibits large nonlinear refractive index (n2 = −1.7642 × 10−12 m2/W) and nonlinear absorption coefficient (β = 1.12 × 10−6 m/W). The negative sign of the nonlinear refractive index n2 indicates that the material exhibits self-defocusing optical nonlinearity. The evaluation of the figure of merit (W = 1.8) shows that the solution of PDPAlq3 is sufficient for application in all-optical switching technology. These results show that the solution of PDPAlq3 have potential application in nonlinear optics. 相似文献
17.
We report on third order optical nonlinear experimental characterization using Z-scan method through focal shift measurements of a converging lens. The sample is fixed in front of a lens and is illuminated by a collimated beam. The shift of the geometrical focus in the nonlinear regime using input Gaussian beams is related to the nonlinear induced dephasing owing to a simple linear relation. Numerical calculations based on the Helmholtz wave equation are performed. Good agreement is obtained between experimental and theoretical results. 相似文献
18.
In this work, nano silver clusters incorporated into europium oxide thin films at a level of 3.8% and 12.5% have been prepared by a vacuum evaporation method on glass and silicon substrates. Samples were investigated by X-ray fluorescence, X-ray diffraction, and linear and nonlinear optical absorption methods. The X-ray diffraction reveals that the Eu oxide of these samples remains amorphous after pre-annealing at 400 °C. The linear optical absorption of the samples shows surface plasmon resonance (SPR) phenomena, which varies with the Ag content of the samples. The optical nonlinear absorption properties of the prepared films were investigated using an open Z-scan technique with cw laser at wavelengths 476 nm and 514 nm. A changeover from reverse saturation absorption (RSA) to saturation absorption (SA) was observed. RSA is attributed to interband transition via two photon absorption. SA is attributed to plasmon bleach. 相似文献
19.
LI Feng YANG Xuedong SONG Yinglin LUI Shutian LI Chunfei 《Chinese Journal of Lasers》1997,6(5):424-428
1.IntroductionLeadphthalocyaninehasreceivedconsiderableattentionasitexhibitsstrongreversesaturableabsorption(RSA)behaviorLI].Thiskindoforganometalliccompoundcanbeusedasopticallimitingdevicetoprotecteyesandsensorsfromlaserhazard.Thenanosecondopticallimitingpropertyofleadphthalocyaninehasbeeninvestigatedyet[2].Inthispaper,thepicosecondopticallimitingbehaviorofleadphthalocyanine(Pbpc(CP)4)ispresentedandtheresultiscomparedwithC6o,areversesaturableabsorptionmaterialwhichhasbeenwidelystudied.The… 相似文献
20.