用Z扫描方法测量掺C60有机改良介质的非线性折射率

用Ｚ扫描方法和波长１．０６４μｍ、脉宽１５０ｐｓ的锁模激光测定了Ｃ６０／ＮＨ２－（ＣＨ２）３－Ｓｉ（ＯＣ２Ｈ５）３（简称Ｃ６０／ＫＨ５５０）溶胶和凝胶的三阶光学非线性系数。理论拟合曲线计算得出，溶胶复合材料的非线性折射率ｎ２＝５．６×１０－１２ｅｓｕ，经两天凝结之后的凝胶复合材料的ｎ２＝６．２×１０－１２ｅｓｕ。在相同的激光强度下溶胶和凝胶的不同透过率归因于溶胶液体对激光的非线性散射。     

Cd_xHg_（1－x）Te／SiO_2固溶体微晶掺杂玻璃三阶非线性光学性质的

本文首次报道了对采用溶胶凝胶和原位生长工艺制备的Ｃｄ_ｘＨｇ_(１－ｘ)Ｔｅ／ＳｉＯ_２固溶体微品掺杂玻璃进行的三阶非线性光学性质实验研究及其结果。利用回返式简并四波混频技术，测得该固溶体掺杂玻璃的三阶非线性极化率的值为１０￣（－１２）ｅｓｕ量级。此结果比纯ＳｉＯ_２基体提高了２个数量级。表明该固溶体掺杂玻璃三阶非线性明显增强，在同样条件下，测得ＣＳ_２的三阶非线性极化率ｘ（３）为（１．７±０．２）×１０￣(－１２)ｅｓｕ，与国际上报道完全一致。     

1－苄基－9－氢富勒烯－60LB多层膜的制备及其光学非线性性质

利用π－Ａ等温线、小角Ｘ射线衍射（ＳＡＸＤ）和光学测量方法研究了一种取代富勒烯（Ｃ６０－Ｂｅ）ＬＢ膜的结构特性。纯Ｃ６０－Ｂｅ分子以体相（ｂｕｌｋｐｈａｓｅ）的形式存在于气－液界面上。氮冠（醚）（ＮＣ）分子作为隔层材料，与Ｃ６０－Ｂｅ分子相混合可以制备性能优良的ＬＢ膜。π－Ａ、吸收和小角Ｘ光衍射测量表明：这种混合膜结构的改善是由于Ｃ６０－Ｂｅ分子镶嵌在ＮＣ分子的双脂链之间造成的。通过测量三次谐波产生（ＴＨＧ）可以推出Ｃ６０－Ｂｅ的三阶非线性系数χ（３）＝２．１×１０－１１ｅｓｕ。     

对称型二烷氨基蒽醌的三阶非线性光学性质研究

研究了对称型二烷氨基蒽醌的三阶非线性光学性质。通过三维简并四波混频实验对１１种低浓度溶液样品的测试，其三阶非线性极化率｜χ（３）｜达１．８～３．４×１０－１３ｅｓｕ，分子的三阶非线性超极化率γ达１．９～３．５×１０－３１ｅｓｕ。讨论了分子结构对三阶非线性光学性质的影响。     

C60固体的光学性质

本文综述了有关Ｃ＿（６０）固体的光学性质最近的研究进展。其中包括Ｃ＿（６０）分子及其固体的非线性光学性质、各种吸收光谱及电子结构，光电导及光电子能谱等方面。     

4－戊基－4＇－氰基联苯液晶的分子二阶非线性光学极化率测量方法

在玻璃衬底上制得单层硬脂酸的Ｌａｎｇｍｕｉｒ－Ｂｌｏｄｇｅｔｔ（ＬＢ）膜，做为４－戊基－４＇－氰基联苯（５ＣＢ）液晶的取向层，在取向层上旋涂一层５ＣＢ液晶，用透射二次谐波方法测量出５ＣＢ液晶分子二阶非线性光学极化率，其值为β＝７×１０－２９ｅｓｕ．对比文献值，测量得到的结果符合较好．     

C60的光物理特性

叙述了近几年来获得的Ｃ６０固体和溶液的吸收光谱、复折射率、三阶非线性光学极化率、光致发光、光激发动力学等一些实验，结果表明Ｃ６０具有独特的光物理特性。     

巴基球C60内嵌原子（Li,Na,K,Rb,Cs;F,Cl,Br,I）的稳定存…

本文用量子化学ＥＨＭＯ／ＡＳＥＤ方法对巴基球Ｃ６０内嵌原子（Ａ＝Ｌｉ，Ｎａ，Ｋ，Ｒｂ，Ｃｓ；Ｆ，Ｃｌ，Ｂｒ，Ｉ）进行了计算。结果表明除Ｌｉ，Ｎａ外，其它元素当置于Ｃ６０笼中心附近时，复合物能量最低，最稳定；对于内嵌Ｌｉ，Ｎａ原子的巴基球（Ｌｉ＠６０）及（Ｎａ＠Ｃ６０），当Ｌｉ，Ｎａ位于围绕中心的一个球壳层（ｒ－１．５Ａ）内时最稳定。     

C60的发现,制备,结构,性质及其潜在应用前景

Ｃ６０是碳的一种新的同素异型结构．本文综述了Ｃ６０的发现与制备方法，Ｃ６０形成的机制与其绪构特征，以及Ｃ６０的性质与其潜在的广阔应用前景．重点介绍用红外（ＩＲ）谱，１３Ｃ核磁共振（ＮＭＲ）谱和Ｘ射线衍射（ＸＤ）谱研究Ｃ６０结构的结果，及掺杂Ｃ６０固体的高温超导电性及其结构的最新研究进展．     

非醚PPQ的三阶非线性光学性质及其时间响应

研究了一种易加工、光吸收小、热稳定性好的材料──非醚聚苯基喹啉（Ｐｏｌｙｐｈｅｎｙｌｑｕｉｎｏｘａｌｉｎｅｓ，缩写ＰＰＱ）的三阶非线性光学性质，用皮秒时间分辨简并四波混频方法测得材料的三阶非线性系数χ（３）～３×１０－１０ｅｓｕ及其时间响应快于３５ｐｓ（受所用激光脉冲宽度的限制）。     

基于热致非线性效应的暗空间光孤子实验研究

实验研究了热致非线性效应作用下，Ｃ＾６０甲苯溶液中强连续激光激发暗空间光孤子的过程，并给出了数值模拟结果。     

Flexible alteration of optical nonlinearities of iodine charge-transfer complexes in solutions

The type of donor used is found to influence greatly the optical nonlinearities of iodine charge-transfer (CT) complexes in solutions for several solvents. The magnitude and sign changes of nonlinear absorption of iodine CT complexes for different solvents as donors are observed, which implies the transition from saturable absorption to reverse saturable absorption. Compared with C60 in toluene, iodine CT complexes with toluene and benzene demonstrate larger reverse saturable absorption. Meanwhile, flexible alteration of optical nonlinearities is easily obtained by adjusting the mixture ratio of different solvents, yielding a prospective means of constructing a nonlinear medium with a large nonlinear coefficient.     

富勒烯分子的光学双稳性

本文采用非线性法布里-珀罗腔的全光光学方法,在C_(60)/C_(70)薄膜中首次观测到双稳开关现象,其开关时间为10ns.     

Z-scan studies and optical limiting of nanosecond laser pulses in neutral red dye

The nonlinear optical absorption, refraction and optical limiting behaviour of an organic dye, neutral red, were investigated under excitation with nanosecond laser pulses at 532 nm. The nonlinear optical responses of the material were studied both in solution and solid film, made in methanol and polyvinyl alcohol, respectively, using single-beam Z-scan technique. The open aperture Z-scans of the solution samples displayed a switch over from saturable absorption to enhanced absorption with increase in input intensity. Theoretical fit to the experimental data indicated that the dominant mechanism of nonlinear absorption is two-photon absorption. The closed aperture Z-scans of both the samples denoted positive nonlinearity, which was three orders larger in magnitude in solid film, compared with that in solution. The results of optical limiting experiments revealed that neutral red exhibited strong optical limiting of nanosecond laser pulses with a threshold lower than that of C₆₀ in toluene.     

Bundling influence on ultrafast optical nonlinearities of single-walled carbon nanotubes in suspension and composite film

Nonlinear optical characteristics of single-walled carbon nanotubes (SWCNTs) dispersed in dichlorobenzene and imbedded in polymer were investigated at 800 nm using the time-resolved optical Kerr gate technique. For systematic study of the influence of SWCNT bundling on optical nonlinearities, SWCNT solutions with different concentrations and a series of SWCNT/polymer composites deposited on glass substrates with different concentrations and thicknesses were prepared. The nonlinear response was comparable to the pulse duration of the laser used (～90 fs) both in SWCNT solutions and SWCNT/polymer composites. Over three orders of magnitude enhancement was observed in the third-order nonlinear susceptibility of SWCNT/polymer composite film compared with that of SWCNT solution. An appreciable reduction of microscopic and macroscopic nonlinearities was observed with increasing SWCNT concentrations due to stronger bundling of SWCNTs.     

足球烯分子三阶非线性光学性质的研究

报道了有关足球烯分子甲苯溶液中简并四波混频实验.测量出足球烯C_(70)分子和C_(60)分子的三阶超极化率张量y_(1111)分量分别为1.2×10~(-30)esu和4.0×10~(-31)esu.对应于固体样品的三阶非线性光学系数X_(1111)分量分别是2.5×10~(-8)esu和8.5×10~(-9)esu.此结果表明了足球烯分子是现有的非线性光学材料中具有较大三阶非共振电子极化率材料之一.文中还利用自由电子模型解释了非线性光学极化率的起源.     

基于富勒烯C_(60)结构体系的金纳米粒子合成物光学非线性研究

使用 5 32nm ,8ns激光脉冲研究了两种新型的基于富勒烯C6 0 结构体系的金纳米粒子合成物的光学非线性 .Z scan实验结果和理论分析的比较表明 ,材料的非线性吸收强烈地依赖于材料中的配合体 ,而非线性折射主要来自金纳米粒子的贡献 .而且与熟知的C6 0 甲苯溶液光限幅特性作了比较 ,分析了光限幅机理 .     

多层纳米硅复合膜的共振光学非线性

本文采用简并四波混频技术在室温下研究晶化a-Si:H/a-SiN_x:H多层纳米硅复合膜三阶非线性光学性质,首次观察到这种多层膜的相位共轭信号,在共振光波波长λ=589nm处实验所用样品的三阶非线性极化率为χ⁽³⁾=1.4×10^-6esu,分析表明其非线性光学响应增强的原因是纳米硅的强量子限域作用.     

Laser ablation of gallium arsenide in different solutions

The optical, structural, and nonlinear optical characteristics of GaAs nanoparticles obtained by laser ablation in different liquids were investigated. Thermally induced self-defocusing in GaAs solutions was observed using both a high pulse repetition rate and nanosecond pulses. In studying the nonlinear optical characteristics of GaAs solutions using picosecond and femtosecond pulses, two-photon absorption was observed. The nonlinear absorption coefficient of an aqueous GaAs solution measured by the Z-scan technique and the nonlinear susceptibility of GaAs nanoparticles were, respectively, 0.7 × 10^?9 cm W^?1 and 2 × 10^?9 esu at a wavelength of 795 nm.     

分散橙25掺杂的聚合物PMMA薄膜全光极化的研究

制备了以分散橙25为客体的掺杂型有机聚合物PMMA薄膜样品，对之进行了全光极化研究，极化使薄膜产生诱导二阶非线性光学效应，种子光的强度越大，其二阶非线性极化率达到的饱和值越大;种子光的位相差、相对强度比、光场强度等因素影响薄膜的二阶非线性的优劣.