共查询到20条相似文献,搜索用时 187 毫秒
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考虑了量子尺寸效应以及来自杂质、粗糙表面和粗糙界面三方面的散射,运用量子统计的格林函数方法和久保公式,计算多层金属圆柱线中的各种散射电导率.计算结果表明,在杂质、表面和界面的弱散射极限下,系统总电导率等于各个子能级通道的电导率之和,而各子能级通道中杂质、表面和界面产生的散射率是可相加的.
关键词: 相似文献
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采用电弱统一标准模型(SM), 对由参与电弱相互作用的各种混合圈构成的电子重整化链图传播子的构架方式作了详细分析, 并完成了有关解析计算, 进而获得了电子重整化链图传播子的解析计算结果. 作者又将此结果应用到Compton散射, 精确计算了电子混合链图传播下Compton散射微分截面的解析结果 . 此外, 作者还将计算结果与最低阶微分截面 和量子电动力学(QED)中电子链图传播下的Compton散射微分截面 做了具体的数值计算与对比分析, 发现 比 能更加精细的反应辐射修正效应. 相似文献
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研究了半空间内(海面,地面)电大尺寸涂敷目标散射的高频求解方法.将半空间并矢格林函数引入物理光学方法中,对半空间复杂环境影响进行考虑,并利用阻抗边界条件考虑涂敷目标表面的复杂电磁散射,推导出半空间物理光学分析方法,同时结合图形电磁学,对半空间电大涂敷目标进行消隐判断,提取像素面元法矢量和深度缓存等有效信息,快速有效地计算了半空间电大涂敷目标的雷达散射截面.数值结果证明了方法的有效性和准确性.
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半空间物理光学方法
半空间并矢格林函数
图形电磁学
雷达散射截面 相似文献
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研究了半空间内复杂导体目标棱边散射的高频求解方法.分析半空间电磁波的传播规律和复杂目标棱边的电磁散射特性,将半空间并矢格林函数引入等效电磁流方法中,给出了基于等效电磁流法和物理绕射理论的半空间棱边散射场计算式,同时结合图形电磁学,对半空间复杂目标进行消隐处理,判断目标的棱边像素及获得棱边参数,与半空间目标的面元散射场相叠加,快速有效地计算了半空间复杂目标的雷达散射截面.数值结果证明了方法的有效性和准确性.
关键词:
半空间等效电磁流方法
半空间并矢格林函数
图形电磁学
雷达散射截面 相似文献
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应用非平衡格林函数方法研究通过环形碳纳米管-量子点耦合系统的介观输运.相干隧穿与环形碳纳米管和量子点各自的能级结构有强烈的依赖关系,阿哈郎诺夫-玻姆效应使能级周期性变化,隧穿电流则随磁通量作周期性振荡.环形碳纳米管的具体纳米结构显示出金属-半导体相变特性,这种行为也在输出电流中体现出来.子系统量子能级的匹配与失配关系在介观输运过程中起重要作用. 相似文献
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The spontaneous emission from a quantum dot embedded in a bi-sphere microcavity is analyzed theoretically. By taking full account of the photon degree of freedom, we derive theoretically the constant of coupling between the quantum dot and the cavity as well as the radiation damping constants, which are used in the conventional cavity QED approach. In addition, we show that the power spectrum of the spontaneous emission at a local observation point is strongly affected by the photon Green function. 相似文献
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Modifications in the spontaneous emission rate of an excited atom that are caused by extinction effects in a nearby dielectric medium are analyzed in a quantummechanical model, in which the medium consists of spherical scatterers with absorptive properties. Use of the dyadic Green function of the electromagnetic field near a dielectric sphere leads to an expression for the change in the emission rate as a series of multipole contributions for which analytical formulas are obtained. The results for the modified emission rate as a function of the distance between the excited atom and the dielectric medium show the influence of both absorption and scattering processes. 相似文献
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Using the eigenfunction expansion of dyadic Green's function in unbounded chiral medium, and the method of scattering superposition, the expressions of dyadic Green's function for the one and two—layer cylindrical chirostrip antennas are derived, when the field sources are placed in any layer of cylindrical chirostrip antenna. Also, using the method of saddle point integration, the asymptotic expression of dyadic Green's function for the wraparound chirostrip antenna is obtained. The results can be directly used to analyse the radiation characteristics of cylindrical chirostrip dipolc antenna, et al. 相似文献
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Hughes S 《Optics letters》2005,30(11):1393-1395
A theoretical quantum-optical study of the modified spontaneous emission dynamics from a single quantum dot in a photonic crystal nanocavity is presented. By use of a photon Green function technique, enhanced single-photon emission and pronounced vacuum Rabi flops are demonstrated, in qualitative agreement with recent experiments. 相似文献
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Carmen Molina-París Paul R. Anderson Stephen A. Ramsey 《International Journal of Theoretical Physics》2001,40(12):2231-2258
The renormalization of a scalar field theory with a quartic self-coupling via adiabatic regularization in a Robertson-Walker spacetime is discussed. The adiabatic counterterms are presented in a way that is most conducive to numerical computations. A variation of the adiabatic regularization method is presented which leads to analytic approximations for the energy–momentum tensor of the quantum field and the quantum contribution to the effective mass of the mean field. Conservation of the energy–momentum tensor for the field is discussed and it is shown that the part of the energy–momentum tensor which depends only on the mean field is not conserved but the full renormalized energy–momentum tensor is conserved, as expected and required by the semiclassical Einstein's equation. It is also shown that if the analytic approximations are used the resulting approximate energy–momentum tensor is conserved. This allows a self-consistent backreaction calculation to be performed using the analytic approximations. The usefulness of the approximations is discussed. 相似文献
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为快速求解亚波长间距分布的理想导体球阵列近区的时间反演电磁场,提出一种基于等效偶极子模型的解析分析方法.首先,通过分析球面波照射理想导体小球的散射场解析解发现,散射场可以近似等效为电磁偶极子辐射场的叠加.等效偶极子的强度与初始激励源的幅度成正比关系.通过建立不同小球等效偶极子矢量间的耦合方程组可以直接求解得到相应矢量的大小.然后,结合时间反演腔理论得到相应的时间反演并矢格林函数,继而得到小球阵列近区的时间反演场分布.最后,通过与数值仿真软件的计算结果进行对比,验证了方法的正确性及高效性.研究表明,时间反演技术结合近场亚波长间距小散射体加载能够实现超分辨率的场聚焦. 相似文献
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A one-dimensional closed interacting Kitaev chain and the dimerized version are studied. The topological invariants in terms of Green's function are calculated by the density matrix renormalization group method and the exact diagonalization method. For the interacting Kitaev chain, we point out that the calculation of the topological invariant in the charge density wave phase must consider the dimerized configuration of the ground states. The variation of the topological invariant is attributed to the poles of eigenvalues of the zero-frequency Green functions. For the interacting dimerized Kitaev chain, we show that the topological invariant defined by Green's functions can distinguish more topological nonequivalent phases than the fermion parity. 相似文献
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We consider the non-Fermi-liquid quantum critical state of the spin-S two-impurity Kondo model and its potential realization in a quantum dot device. Using conformal field theory and the numerical renormalization group, we show the critical point to be identical to that of the two-channel Kondo model with additional potential scattering, for any spin S. Distinct conductance signatures are shown to arise as a function of device asymmetry, with the square-root behavior commonly believed to arise at low-energies dominant only in certain regimes. 相似文献