交流源作用下介观RLC电路系统量子态随时间的演化

根据量子不变量理论，同时考虑介观电容器极板间电子波函数的耦合作用和电路的耗散,研究介观RLC电路系统在交流电流源作用下动力学的演化过程，并且得到描述系统量子态随时间的演化算符.进一步的分析结果表明，介观RLC电路系统的波函数将由任意的初态演化到一般的压缩态. 关键词： 介观RLC电路 交变电源 不变量理论 时间演化算符     

米散射理论在新型导光板中的应用

根据米散射理论,提出了新型导光板的设计思路,计算并分析了对于一定波长的入射光,不同粒径的微粒的散射特性。总结了随着微粒粒径的变化,散射效率、消光效率与背向散射效率的变化规律,分析了散射过程中的偏振度随粒子粒径几散射角变化的情况,同时模拟计算了多个微粒对同一波长的入射光经过多次散射后的概率统计结果。     

Highly selective surface-wave resonators for terahertz frequency range formed by metallic Bragg gratings

In the frame of the quasi-optical approach we solve the diffraction problem and describe surface modes confined at a metallic plate with a shallow grating of finite length. We prove that such planar grating can form a highly selective surface-wave Bragg resonator. For a given material conductivity and grating length, we find the optimum corrugation depth that provides the maximum value of Q factor. These results are applicable for developing resonators for terahertz frequency bands.     

CPT violation does not lead to violation of Lorentz invariance and vice versa

We present a class of interacting nonlocal quantum field theories, in which the CPT invariance is violated while the Lorentz invariance is present. This result rules out a previous claim in the literature that the CPT violation implies the violation of Lorentz invariance. Furthermore, there exists the reciprocal of this theorem, namely that the violation of Lorentz invariance does not lead to the CPT violation, provided that the residual symmetry of Lorentz invariance admits the proper representation theory for the particles. The latter occurs in the case of quantum field theories on a noncommutative space–time, which in place of the broken Lorentz symmetry possesses the twisted Poincaré invariance. With such a CPT-violating interaction and the addition of a C-violating (e.g., electroweak) interaction, the quantum corrections due to the combined interactions could lead to different properties for the particle and antiparticle, including their masses.     

Matone's Relation ofN =2 Super Yang-Mills and Spectrum of Toda Chain

InN=2 super Yang-Mills theory, the Matone's relation relates instanton corrections of the prepotential to instanton corrections of scalar field condensation <
Trφ²>. This relation has been proved to hold for Omega deformed theories too, using localization method. In this paper, we first give a case study supporting the relation, which does not rely on the localization technique. Especially, we show that the magnetic expansion also satisfies a relation of Matone's type. Then we discuss implication of the relation for the spectrum of periodic Toda chain, in the context of recently proposed Nekrasov-Shatashvili scheme.     

Magnetic field effect in photodetachment from negative ion in electric field near metal surface

Based on the closed-orbit theory, the magnetic field effect in the photodetachment of negative ion in the electric field near a metal surface is studied for the first time. The results show that the magnetic field can produce a significant effect on the photodetachment of negative ion near a metal surface. Besides the closed orbits previously found by Du et al. for the H in the electric field near a metal surface (J. Phys. B 43 035002 (2010)), some additional closed orbits are produced due to the effect of magnetic field. For a given ion-surface distance and an electric field strength, the cross section depends sensitively on the magnetic field strength. As the magnetic field strength is very small, its influence can be neglected. With the increase of the magnetic field strength, the number of the closed orbits increases greatly and the oscillation in the cross section becomes much more complex. Therefore we can control the photodetachment cross section of the negative ion by changing the magnetic field strength. We hope that our results may guide future experimental studies for the photodetachment process of negative ion in the presence of external fields and surfaces.     

Adsorption of sodium ions and hydrated sodium ions on a hydrophobic graphite surface via cation-π interactions

Using density functional theory computation, we show that sodium ions and hydrated sodium ions can be strongly adsorbed onto a hydrophobic graphite surface via cation-π interactions. The key to this cation-π interaction is the coupling of the delocalized π states of graphite and the empty orbitals of sodium ions. This finding implies that the property of the graphite surface is extremely dependent on the existence of the ions on the surface, suggesting that the hydrophobic property of the graphite surface may be affected by the existence of the sodium ions.     

不稳定分布的碳烟消光表征方法及规律分析

碳烟的消光表征方法有很多种,但对于评价不稳定分布的碳烟体系,需要花费较大的代价。基于RDG-FA理论提出了一种相对简便易行的适用于不稳定分布碳烟的消光表征方法,即以碳烟的质量浓度权重的平均质量消光系数来评价碳烟的消光特性。根据理论推导,碳烟的消光系数为平均质量消光系数和总质量浓度之积,而平均质量消光系数表达式中的各项均可通过理论分析、计算和实验方法得到。另外,对平均质量消光系数随碳烟粒径和聚合粒子尺寸的变化规律进行了理论分析,预测随着碳烟粒径和聚合粒子尺寸减小,碳烟的平均质量消光系数先快速减小,然后进入缓变区,慢慢减小。     

路易氏剂红外吸收截面积的测定与光谱模拟

采用长程傅里叶红外光谱仪在600～1 600 cm-1波段内对不同浓度路易氏剂-1的气相红外透射光谱进行了测量,其特征频率为814,930,1 563 cm-1;并运用比尔-朗伯定律计算了对应特征频率的红外吸收截面积σ值,依次为3.89±0.01, 1.43±0.06, 4.47±0.05(×10-20 cm2·molecule-1)。路易氏剂-1测量光谱在1 158和1 288 cm-1处也有微弱的吸收峰。利用Gaussian09软件包中的密度泛函理论对系列路易氏剂的红外光谱进行理论模拟,其稳定构型和振动频率在b3lyp/6-311+g(d,p)水平上计算。并利用可视化软件Gaussview5.08对各频率的振动模式进行归属。理论计算的红外光谱和实测光谱在600～1 600 cm-1波段内非常吻合,特征频率的相关系数为0.999 1。计算光谱还发现了0～600 cm-1波段内与砷原子有关的振动频率,为293,360和374 cm-1。用最小二乘法处理试验和计算结果中的特征频率,得到了适合路易氏剂-1的红外光谱频率矫正因子为0.977。利用该矫正因子对路易氏剂-1,路易氏剂-2,路易氏剂-3的红外光谱计算频率进行矫正。结果表明获得的路易氏剂理论红外吸收光谱可为该系列化合物的结构性质预测和远程红外光谱监测等提供参考。