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111.
112.
Newton-Leibniz integration rule only applies to commuting functions of continuum variables, while operators made of Dirac’s symbols (ket versus bra, e.g., |q〉〈q| of continuous parameter q) in quantum mechanics are usually not commutative. Therefore, integrations over the operators of type |〉〈| cannot be directly performed by Newton-Leibniz rule. We invented an innovative technique of integration within an ordered product (IWOP) of operators that made the integration of non-commutative operators possible. The IWOP technique thus bridges this mathematical gap between classical mechanics and quantum mechanics, and further reveals the beauty and elegance of Dirac’s symbolic method and transformation theory. Various applications of the IWOP technique, including constructing the entangled state representations and their applications, are presented. 相似文献
113.
114.
A multiple image cryptosystem based on different apertures in an optical set-up under a holographic arrangement is proposed. The system is a security architecture that uses different pupil aperture mask in the encoding lens to encrypt different images. Based on this approach multiple encryption is achieved by changing the pupil aperture arrangement of the optical system among exposures. In addition to the classical speckle phase mask, the geometrical parameters characterizing the apertures are introduced to increase the system security. Even when an illegal user steals the speckle phase mask, the system cannot be broken into without the correct pupil geometrical parameters. The experimental set-up is based on a volume photorefractive BSO crystal as storing device. Information retrieval is done via a phase conjugation operation. We also have to stress that the multiple storage under this scheme, is only possible with the help of the aperture mask. Simulation and experimental results are further introduced to verify the proposed method. 相似文献
115.
We reveal that for a realistic system, interference effects are obtained such as the suppression of central line and inner sidebands and the narrowing of the outer fluorescence sidebands. For this purpose, we consider a spontaneous decay from an excited state to a metastable state when the excited and metastable states are resonantly coupled to an auxiliary metastable state by a laser field and a microwave field, respectively. The fluorescence spectrum evolves from a five-peaked structure into a doublet of ultrasharp lines as the ratio of the laser field Rabi frequency to the microwave Rabi frequency is decreased. The physical origin is presented in terms of dressed states. 相似文献
116.
Faisal A.A. El-Orany 《Optics Communications》2006,263(2):235-238
We prove that the revival-collapse phenomenon occurring in the atomic inversion of the two-photon Jaynes-Cummings model, when the mode is initially prepared in the coherent state and the atom is in the excited state, can be obtained from the evolution of the quadrature squeezing of the four-photon Jaynes-Cummings model. 相似文献
117.
We have applied Engel-Vosko exchange energy within density functional theory, to calculate the electronic structure and the optical properties of BaX (X = Te, Se, and S) compounds via full potential linearized augmented plane wave method. We have found that this improves the band gap results comparing to our previous work in which we had made use of Perdew et al. exchange energy functional. We have also calculated the dielectric constant of these compounds, using both Perdew et al. and Engel-Vosko schemes. It is shown that Engel-Vosko exchange energy functional leads to a better result. We have also reported the effect of spin-orbit coupling on the results. 相似文献
118.
We consider some Sobolev-type spaces and obtain a necessary and sufficient condition for their embedding in a Lebesgue space. 相似文献
119.
This paper gives some global and uniform convergence estimates for a class of subspace correction (based on space decomposition) iterative methods applied to some unconstrained convex optimization problems. Some multigrid and domain decomposition methods are also discussed as special examples for solving some nonlinear elliptic boundary value problems.
120.
本文给出了一个关联图为圈的非负、半正定矩阵A为完全正的一个充要条件.我们还证明了这样的矩阵A(当A为完全正时)的分解指数即为A的阶数. 相似文献