Secondly , the third order nonlinear optical properties of these compounds are studied under the excitation of ps pulsed laser with the wavelength of 1064nm using z - scan technique , nonlinear refractive indices and nonlinear absorption coefficients are calculated according to the z - scan experiment curves of the compounds . all the three compounds have self defocusing characters and two photon absorptions . lastly , nonlinear refraction and absorption properties of these compounds are studied by z - scan technique under the excitation of ps pulsed laser with the wavelength of 532nm the self defocusing and reverse saturation absorption are found in these compounds 根据实验曲线计算了它们在1064nm下的三阶非线性折射率和非线性吸收系数,三种化合物都具有自聚焦特性,并且在该波长下,三种化合物均具有双光子吸收,最后,以皮秒脉冲的532nm为激发波长,采用z扫描方法,研究了三种金属有机化合物的非线性折射和非线性吸收性质,在该波长下三种化合物仍然表现为自聚焦特性,且其吸收为反饱和吸收。
Starting from the theory of two photoionization , we simplified the model of the ultraviolet light source , derived the equation for the spatial distributions of the initial electron density between the main electrodes , and then gave a simple method to homegenize the spatial distribution of the initial electron density between the main electrodes 本文从光离化的双光子吸收这一理论出发,简化紫外光源模型后,导出了主电极间初始电子密度的空间分布规律并给出了使其空间分布均匀化的简单方法。
It has some advantages other than inorganic materials , such as quick response , large electro - optical coefficient , wide transparence , simple manufacture , low cost and easy for integration , etc . some pyridinium salts with " d - - a " structure have very excellent tpa and up - conversion fluorescence properties , so they are the possible candidates to be used to make tpa up - conversion dye lasers 这类材料具有响应速度快、电光系数大、透光波段宽、制备简单、成本低廉、易于集成等优点。 “ d - - a ”型的吡啶盐系列染料具有非常优秀的双光子吸收和激光上转换性能,是双光子上转换激光器的候选材料。
The study result indicate that , the asymmetry substituted molecules display larger two - photon absorption cross sections than the symmetry substituted molecules , which illustrates that the effect of the different substitutions on molecule ' s two - photon absorption property is related to the property of molecule ' s - center 98程序包上完成。结果表明在此五种化合物中具有不对称结构的分子具有更大的双光子吸收截面。因此,分子的对称性是否比不对称性更有利于增大分子的双光子吸收截面,还与分子的。
The molecules we studied are a series of trans - stilbene derivatives . first , we applied dft method optimized the new synthesis molecule 4 , 4 ' - bis ( dimethylamino ) stilbene ' s structure , and used few states model calculated its tpa cross section . the results agree well with the experiment data 首先,我们在密度泛函理论( densityfunctiontheory )的水平上对最近合成的分子材料4 , 4 -二甲氨基二苯乙烯的结构进行了优化,然后采用少态模型方法计算了分子的双光子吸收截面,得到了与实验符合很好的结果。
We have calculated one - and two - photon absorption cross sections of the lowest excited states of a series of molecules combined with benzene , stilben , thiophene as center attached with amine , diphenylamine , diethylamine as electron - donor and nitryl as electron - acceptor ; the effects of molecular length , n center and electron - donor on two - photon absorption cross sections have been studied and all calculations have been carried out using the density functional theory at an ab initio level . it is found that the molecular length and the one - photon absorption intensity are quite strongly c orrelated factors , and that a corresponding correlation for the two - photon absorption is decreasing . it is also found that a most crucial role for the two - photon absorption is played by the n center 我们分别以苯、二苯乙烯、噻吩为中心,氨基、二苯氨基和二乙氨基为电子给体,硝基为电子受体组合形成的分子为研究对象,在从头计算的水平上用密度泛函理论计算了这些分子在低激发态下的单、双光子吸收强度,重点研究了分子的长度、中心和给体的供电子能力对分子单、双光子吸收的影响。研究结果表明,分子长度与单光子吸收强度之间有密切关系,而在双光子吸收中这种关系较弱;中心在双光子吸收中具有重要的作用;在中心和受体一定的情况下,增加给体的供电子能力,可提高双光子吸收强度。
Such measares as elecbe spetri , fluorescence spectruin in solution and in solid , two - photon absorphon , ophcal lindting are employed in these studies . we find that all of these compounds have ligh - excited emitting properies and non - linear absorphon properties at different extents . all of this properties lay out applied prospects of them in opt - eiectron funchonal materials area 分为电子光谱,液体荧光,固体荧光,双光子吸收,光限幅和z扫描研究,发现产物都有光致发光性质,并有不同程度的非线性吸收性质,展示了其在光学材料领域的应用前景。
We analyze the influences of the perturbed energy - level space and superposion , laser power and intermediate level offset on quantum interference . experimentally , in the sodium dimmer rhomb - type four - level system with a pair of perturbed levels , the interference enhancement of two - photon absorption caused by coherent superposition of the perturbed levels is experimentally observed 分析了微扰能级的间隔和叠加程度、激光功率以及中间能级的失谐对量子干涉效应的影响,实验上观察了包含有一对微扰叠加中间能级的菱形四能级系统中的双光子激发现象,发现微扰能级的相干叠加可增强双光子吸收。