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1.
Recently, π-conjugated polymers with large π-electrondelocalization have received much attention because oftheir larger and ultra faster nonlinear optical (NLO)response due to the distortion of π-conjugated elec-tronic charge distribution along the main chain[1-3].Poly(p-phenylene vinylene) (PPV) and its derivativesare typical π-conjugated polymers that have been de-scribed in the literature for the possibility of using themin light-emitting device and large-area multicolor dis-play, whi…  相似文献   
2.
聚苯胺-富勒烯复合膜的光电响应   总被引:3,自引:0,他引:3  
通过溶液共混方法制备了聚苯胺(PANI)-富勒烯复合膜, 并用IR、XRD、UV-Vis等技术对其进行表征.红外光谱表明聚苯胺与C60之间存在相互作用且表现为掺杂态聚苯胺红外谱图样.X射线衍射表明复合体材料的结晶性能增强.光致发光谱表明聚苯胺与C60分子之间存在有效光诱导电荷分离现象.光电响应实验表明复合体薄膜的光吸收增强, 光电流增大, 说明聚苯胺-富勒烯复合膜受光照射后发生了光诱导电荷分离现象, C60掺杂聚苯胺有助于改善光伏特性.  相似文献   
3.
李宝铭  吴洪才  李晓奇  易文辉 《光子学报》2006,35(10):1522-1525
通过双醚化反应、氯甲基化反应以及在强碱性条件下进行的脱氯化氢反应制备聚(2-甲氧基-5-丁氧基)对苯乙炔(PMOBOPV)、聚(2-甲氧基-5-己氧基)对苯乙炔(PMOHOPV)、聚(2,5-二丁氧基)对苯乙炔(PDBOPV)和聚(2,5-二己氧基)对苯乙炔(PDHOPV)等四种可溶性聚对苯乙炔(PPV)衍生物,通过紫外-可见吸收光谱对产物分子结构进行表征.结果显示,PMOBOPV、PMOHOPV、PDBOPV和PDHOPV的共轭π电子发生π → π* 跃迁的吸收峰分别位于491 nm、495nm、504nm和510nm处,相应的光学禁带宽度分别为2.23eV、2.18eV、2.12eV和2.07eV.利用简并四波混频技术测量PPV衍生物的三阶非线性光学性能,探讨了分子结构对PPV衍生物三阶非线性极化率(χ(3))的影响.研究发现,激发波长为532 nm时,PMOBOPV、PMOHOPV、PDBOPV和PDHOPV的共振χ(3)值分别为3.45×10-10、5.13×10-10、7.15×10-10和9.61×10-10 esu;激发波长为1064 nm时,它们的非共振χ(3)值分别为1.09×10-11、1.42×10-11、1.62×10-11和2.14×10-11 esu.  相似文献   
4.
合成了一系列聚芳香杂环甲烯,包括聚吡咯甲烯和聚噻吩甲烯.采用四波混频法研究材料的共振三阶非线性光学效应(λ=532nm),其共振二阶超分子极化率γ三阶非线性光学系数分别达到10-30esu和10-8esu.选择具有良好溶解性、成膜性的聚吡咯对二甲氨基苯甲烯(PPDMAB),采用飞秒时间分辨光克尔效应方法研究材料的非共振三阶非线性光学效应(λ=790nm).实验表明,翠绿亚胺碱溶液的光克尔信号仅表现一超快响应的成分,归功于π电子云扭转产生的非共振激发.PPDMAB的非共振二阶超分子极化率γ三阶非线性光学系数分别达到γ=5.78×10-32esu和χ(3)=1.26×10-10esu.  相似文献   
5.
We have employed phase-diffusion model to study the effects of laser field correlation on the Raman-enhanced nondegenerate four-wave mixing (RENFWM). The different roles of the field fluctuations have been pointed out. A time-delayed method has been proposed to suppress the thermal background. An enhancement of the ratio between the resonant and nonresonant RENFWM signal intensities was found as the time delay is increased when the laser has broadband linewidth. When the lasers have Gaussian line shape, we also present a second-order coherence function theory to elucidate the temporal asymmetry behavior of the RENFWM.  相似文献   
6.
聚对苯乙炔;电导率;三阶非线性极化率;简并四波混频;可溶性聚(2-甲氧基-5-辛氧基)对苯乙炔的合成及其导电和三阶非线性光学性能  相似文献   
7.
We have employed second-order coherence function theory to study the nonlinear effects of third-and fifth-order on polarization beats in a four-level system (TPBFS and FPBFS). It is found that the different temporal behavior of the beat signal in TPBFS and FPBFS depends on the stochastic properties of the lasers and transverse relaxation rate of the transition. We have considered the cases that pump beams have either narrow band or broadband linewidth and found that for both cases a Doppler-free precision can be achieved in the measurement of the energy-level difference between two excited states which are dipolar forbidden from the ground state. We also discussed the spatiall modulation behavior of the beat signal.  相似文献   
8.
云大钦  封伟  吴洪才  刘效增  强军锋 《中国物理 B》2010,19(1):17304-017304
Nanocomposites of poly[(2-methoxy,5-octoxy)1,4-phenylenevinylene]-zinc selenide (MOPPV-ZnSe) are synthesized by mixing the polymerization of 1,4-bis (chloromethyl)-2-methoxy-5-octoxy-benzene in the presence of ZnSe quantum dots. The resulting MOPPV-ZnSe nanocomposites possess a well-defined interfacial contact, thus significantly promoting the dispersion of ZnSe within the MOPPV matrix and facilitating the electronic interaction between these two components. Raman and UV-visible absorption spectra are influenced by the incorporation of ZnSe nanocrystals. High-resolution transmission electron microscopic and tapping-mode atomic force microscopic results show clearly the evidence for phase-segregated networks of ZnSe nanocrystals, which provide a large area of interface for charge sep- aration to occur. Steady-state spectra of MOPPV-ZnSe nanocomposites are markedly quenched by the introduction of intimate polymer/ZnSe junctions. Time-resolved photoluminescence measurements show that the lifetime decays quickly, which further confirms the occurrence of charge transfer in MOPPV-ZnSe nanocomposites.  相似文献   
9.
Based on the second-order coherence function, we have studied a phase-conjugate ultrafast modulation spectroscopy due to the interference between the fifth- and fifth-order optical polarizations in cascade three-level Doppler-broadened system. It is found that the temporal behaviour of the beat signal depends on the stochastic properties of the lasers and the transverse relaxation rate of the transition. The beat signal depends on the second-order coherence function, which is determined by the laser line shape. Since different stochastic models of the laser field only affect higher than second-order coherence functions, they have little influence on the general temporal modulation behaviour of the beat signal. The cases that pump beams have either narrow band or broadband linewidth are considered and it has been found that for both cases the overall accuracy for the energy-level difference measurement is determined by the homogeneous linewidths of the optical transitions. Finally, the spatial modulation behaviour of the beat signal has also been discussed.  相似文献   
10.
将4,4'-二氨基三苯甲烷(DTM)单体与均苯四甲酸酐(PMDA)进行缩聚反应,再与对-硝基苯基重氮氟硼酸盐进行重氮偶合反应,然后经酰亚胺化合成了侧链含偶氮苯发色团的聚酰亚胺非线性光学材料(NLOPI).通过红外光谱对产物进行了结构表征.对产物的紫外-可见吸收光谱研究发现,在330和490nm处出现侧链偶氮苯发色团的特征吸收.通过简并四波混频方法(DFWM)测定侧链含偶氮苯发色团的聚酰亚胺薄膜的三阶非线性极化率χ(3)=4.58×10-18m2/W.在DFWM中,前向泵浦光If和探测光Ip是主要的写入光,而后向泵浦光Ib是主要的读出光.证实了光致偶氮分子的顺反异构能够导致光信息存储的特性.  相似文献   
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