q－玻色湮没算符高次幂的本征态及其性质

研究ｑ－玻色湮没算符高次幂（ｋ≥３）的正交归一本征态的数学结构，在此基础上讨论了它们的数学性质及其ｑ－压缩和振幅Ｎ次方压缩特性．发现它们能组成一个完备的希尔伯特（Ｈｉｌｂｅｒｔ）空间；且当ｋ为偶数时，这些本征态均可存在振幅Ｎ次方压缩．     

脉冲激光在有机分子材料中的共振传播

利用麦克斯韦-布洛赫耦合方程,研究了激光脉冲在4,4′-二甲氨基二苯乙烯分子材料中的共振传播,探讨了激光脉冲在传播中的时空演化情况.在数值计算中考虑了各种阻尼效应.     

THE AMPLITUDE-N-TH POWERED SQUEEZING OF AN ELECTROMAGNETIC FIELD IN THE MULTIPHOTON JAYNES-CUMMINGS MODEL INTERACTING WITH THE SUPERPOSITION STATE

We have studied the properties of the amplitude-N-th powered squeezing of an elec-tromagnetic field in the k-photon Jaynes-Cummings model of an atom initially being in the ground state and coupling with the superposition state. The results show that, under the condition of n≥k, where n is the photon number of the superposition state, the field exhibits not only the amplitude-N = n-th powered squeezing but also the amplitude-N = (n/2)-th powered squeezing for even n. The variations of the amplitude-N-th powered squeezing of the field with the powers N and k are discussed.     

分子线的电子输运特性

从第一性原理出发利用密度泛函理论计算了共扼分子2氨基5硝基1,4二乙炔基4′苯硫醇基苯(2amino5nitro1,4diethyny4′benzenethiolbenzene)的电子结构,并利用前线轨道理论和微扰理论定量地确定了该分子与金表面的相互作用能常数.然后,利用弹性散射格林函数方法研究了该分子与金表面形成的分子线的伏安特性.计算结果表明,分子通过硫氢官能团可以很强地吸附于金表面上,形成以共价键为主的混合键,从而为电子的转移提供了通道.当外加偏压很低时,分子线的电流存在禁区,禁区的宽度约08eV. 关键词： 化学吸附 分子线 分子电子学     

Solvent effects on structure and optical properties of a D- π-A azobenzene dye

Time-dependent hybrid density functional theory in combination with Onsager reaction field model and super-molecular model has been applied to study solvent effects on the geometrical and electronic structures, as well as one/two-photon absorption properties, of 4-（N-（2-hydroxyethyl）-N-methyl）-amino-4＇-nitroazobenzene. It is found that the short-range interaction has a large effect on the electronic structure of the solute molecule, namely, large red-shift of the maximum one-photon absorption is induced by hydrogen bonding. The solute molecule has a large two-photon absorption cross section, which is enhanced by the solvent effect. The computational results are in good agreement with measurements.[第一段]     

不同取向的1,8-辛二硫醇分子的伏安特性研究

以1,8-辛二硫醇分子为研究对象,在第一性原理基础上,利用弹性散射格林函数方法,研究了1,8-辛二硫醇分子在金原子团簇上不同取向对该分子结电输运特性的影响.计算结果表明,分子与金原子团簇表面之间方位角的不同会导致分子结构、电子结构的改变,从而影响分子体系的电输运特性.当1,8-辛二硫醇分子S-S轴线与金(111)面的法线成25°夹角时,所得到的电流-电压曲线与实验值符合较好.     

分子间相互作用对硫醇分子膜电输运性质的影响

利用密度泛函理论和弹性散射格林函数方法,对硫醇分子膜的电学特性进行模拟.计算结果表明,由于分子间的相互作用,导致分子膜的导电能力比单分子提高2~3个数量级.分子结的导电能力随着压力增加而增加,电极距离的变化使分子与电极以及分子间的耦合增强、分子结的链内隧穿和链间隧穿几率增大,导致电流增加.     

有机分子电子输运性质的计算与分析

从第一性原理出发,采用杂化的密度泛函理论和弹性散射格林函数法,计算有机分子4,4'-二巯基二苯醚分子的电子结构并研究其电子输运性质.计算结果表明,电场对分子系统电子结构有明显的影响,电流、电导表现为非线性变化,与不考虑电场作用时相比,更为接近实验结果.     

Theoretical Studies on One-photon and Two-photon Absorption Properties of Pyrene-core Derivatives

The analytic response theory at density functional theory level is applied to investigate one-photon and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical results show that there are a few charge-transfer states for each compound in the lower energy region. The one-photon absorption properties of the five investigated compounds are highly consistent with those given by experimental measure-ments. The two-photon absorption intensities of the compounds are greatly enhanced with the increments of the molecular sizes, in which the two-photon absorption cross section of the four-branched compound is about 5.6 times of that of the mono-branched molecule. Further-more, it is shown that the two-photon absorption properties are sensitive to the geometrical arrangements.     

The aggregation effects on the two-photon absorption properties of para-nitroaniline polymers by hydrogen-bond interactions

This paper has theoretically designed a series of aggregate polymers on the basis of several para-nitroaniline monomers by hydrogen-bond interactions. At the level of time-dependent hybrid density functional theory, it has optimized their geometrical structures and studied their two-photon absorption (TPA) properties by using analytical response theory. The calculated results exhibit that the aggregation effects not only bring out the considerable red shift of the excited energies but also greatly enhance the TPA intensities of the aggregate polymers in comparison with the para-nitroaniline monomer. The aggregate configurations also have an important influence on the TPA abilities of the polymers; the trimer has the largest TPA cross section. The electron transitions between the molecular orbits involving the strong TPA excitations of the trimer are depicted to illuminate the relationship between the intermolecular charge transfer and the TPA property.