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31.
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33.
The well-posedness of the initial-boundary value problem of the time-varying
linear electromagnetic field in a multi-medium region is investigated.
Function spaces are defined, with Faraday's law of
electromagnetic induction and the initial-boundary conditions considered
as constraints. Gauss's
formula applied to a multi-medium region is used to derive
the energy-estimating
inequality. After converting the initial-boundary conditions into
homogeneous ones and analysing the characteristics of an operator introduced
according to the total current law, the existence, uniqueness and stability
of the weak solution to the initial-boundary value problem of
the time-varying linear electromagnetic field are proved. 相似文献
34.
磁场对非对称量子点中极化子性质的影响 总被引:3,自引:1,他引:3
采用线性组合算符和幺正变换方法研究磁场对非对称量子点中弱耦合磁极化子性质的影响.导出了非对称量子点中弱耦合磁极化子的振动频率、基态能量和基态结合能随量子点的横向和纵向有效受限长度、磁场和电子-声子耦合强度的变化关系.数值计算结果表明:非对称量子点中弱耦合磁极化子的基态能量和基态结合能随量子点的横向和纵向有效受限长度的增加而迅速增大.随回旋频率的增加而增大,随电子-声子耦合强度的增加而减小. 相似文献
35.
Two counter-propagating evanescent beams are used to align and manipulate polystyrene particles on a prism surface. Since the radiation pressure transferred laterally from the evanescent wave is negated on both sides, particles can be stably aligned. By projecting a circular and a linear beam spot onto the interface, both multiple and single arrays of particles are achieved. Arrays of particles trapped on the interface can be easily moved adjusting the intensity of incident beams on either side. We also simulate electromagnetic distribution of scattering light that is converted from the evanescent wave using the FDTD method. The results show that scattering light converts from an evanescent wave propagating through a particle array and has a distance longer than that propagating from a normal evanescent wave. 相似文献
36.
Stability analysis and control synthesis of uncertain Roesser-type discrete-time two-dimensional systems 下载免费PDF全文
We study the stability analysis and control synthesis of uncertain discrete-time two-dimensional(2D) systems.The mathematical model of the discrete-time 2D system is established upon the well-known Roesser model,and the uncertainty phenomenon,which appears typically in practical environments,is modeled by a convex bounded(polytope type) uncertain domain.The stability analysis and control synthesis of uncertain discrete-time 2D systems are then developed by applying the Lyapunov stability theory.In the processes of stability analysis and control synthesis,the obtained stability/stabilzaition conditions become less conservative by applying some novel relaxed techniques.Moreover,the obtained results are formulated in the form of linear matrix inequalities,which can be easily solved via standard numerical software.Finally,numerical examples are given to demonstrate the effectiveness of the obtained results. 相似文献
37.
Efficient three-step entanglement concentration for an arbitrary four-photon cluster state 下载免费PDF全文
We propose an entanglement concentration protocol to concentrate an arbitrary partially-entangled four-photon cluster state.As a pioneering three-step entanglement concentration scheme,our protocol only needs a single-photon resource to assist the concentration in each step,which makes this protocol more economical.With the help of the linear optical elements and weak cross-Kerr nonlinearity,one can obtain a maximally-entangled cluster state via local operations and classical communication.Moreover,the protocol can be iterated to obtain a higher success probability and is feasible under current experimental conditions. 相似文献
38.
Impacts of higher-order dispersions and saturable nonlinearities on modulation instability in negative-refractive metamaterials 下载免费PDF全文
On the basis of the standard linear stability analysis and Drude electromagnetic model,the impacts of higher-order dispersions and three kinds of typical saturable nonlinearities on modulation instability(MI) have been analyzed and calculated for negative-refractive metamaterials(MMs).Our results show that the MI gain spectra consist of only one spectral region instead of one or two regions in ordinary materials,which may be close to or far from the zero point.Particularly,the spectrum far from the zero point has a high cut-off frequency but a narrow spectral width,which is obviously beneficial to the generation of high-repetition-rate pulse trains.Moreover,MI characteristics here will vary with the normalized angular frequency which can be modified by adjusting the structures of negative-refractive MMs,signifying the controllability of bistable solitons and MI based applications.The effects of saturable nonlinearities are similar to those in ordinary materials. 相似文献
39.
采用线性组合算符与变分相结合的方法讨论了无限深量子阱中强耦合束缚极化子的温度效应.给出了无限深量子阱中束缚极化子的基态能量和振动频率随温度和阱宽的变化关系.对RbCl晶体进行了数值计算,结果表明:当温度升高时,量子阱中强耦合束缚极化子的振动频率增大,基态能量的绝对值增大;并且基态能量的绝对值随阱宽增大而增大. 相似文献
40.
比值导数法矿物组分光谱解混模型研究 总被引:4,自引:0,他引:4
矿物丰度含量的精确分析是高光谱遥感技术定量分析中的难点。将化学领域的比值导数光谱算法进行总结,将其引入遥感反射率光谱分析,提出了基于线性光谱混合模型的比值导数光谱解混模型,并利用石膏和绿帘石粉末混合物进行了模型的精度分析。实验结果表明,矿物粉末混合物在不同波段其光谱混合特性有所不同,其中部分波段有较强的线性混合特征。采用部分强线性混合波段进行光谱解混,可以取得比全波段解混算法更好的结果。比值导数法光谱解混模型简洁,可以得到高精度的矿物成分反演结果,对于固定端元组成的混合光谱定量分析有较大潜力。 相似文献