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81.
82.
引入平移激发压缩真空态D(z)a\+\{+m\}S(r)|0〉,并讨论它的一些基本性质.利用正规 乘积内的积分技术,证明了其完备性.平移激发以后,与压缩真空态相比较,光子数分布 的振荡性质更加显著.与压缩真空态的光子总是聚束的性质不同,在平移参量|z|和激发 数m都较小时,平移激发压缩真空态的光子统计关联可以呈现反聚束效应.计算了它的准 概率分布函数(Q函数和Wigner函数),并讨论了它们对各参量的依赖关系,从Wigner函数可 以清楚地看出该量子态的非经典特性.
关键词: 相似文献
83.
Using the technique of integration within an ordered product of operators, we construct a new common eigenvector set of the complex scalar fields φ(x) and φ?(x), which is a set of particle-antiparticle correlated states. On the basis of the new eigenstates we develop the path integral formuation. The new eigenvectors' properties are investigated, they are qualified to be a new representation. 相似文献
84.
Cooper-Pair Number-Phase Quantization for a Mesoscopic LC Circuit Including a Josephson Junction 下载免费PDF全文
By introducing the entangled state representation and Feynman assumption that 'electron pairs are bosons, ..., a bound pair acts as a Bose particle ', we construct an operator Hamiltonian for a mesoscopic inductance-capacitance (LC) circuit including a Josephson junction, then we use the Heisenberg equation of motion to derive the current equation and the voltage equation across the inductance as well as across the Josephson junction. The result manifestly shows how the junction voltage is affected by the capacitance coupling. In this way the Cooper-pair number-phase quantization for this system is completed. 相似文献
85.
Based on the technique of integration within an ordered product of operators we investigate a completeness relation of pure states (such as the coordinate eigenstate, the momentum eigenstate and the coherent state) into normally ordered Gaussian forms. The Weyl ordering invariance under similarity transformations is employed to reveal physical meaning of a kind of normally ordered Gaussian operators, which have the similar forms to the bivariate normal distributions in statistics, i.e., the thermo mixed state density matrix. 相似文献
86.
Time evolution law of a two-mode squeezed light field passing through twin diffusion channels 下载免费PDF全文
We explore the time evolution law of a two-mode squeezed light field(pure state)passing through twin diffusion channels,and we find that the final state is a squeezed chaotic light field(mixed state)with entanglement,which shows that even though the two channels are independent of each other,since the two modes of the initial state are entangled with each other,the final state remains entangled.Nevertheless,although the squeezing(entanglement)between the two modes is weakened after the diffusion,it is not completely removed.We also highlight the law of photon number evolution.In the calculation process used in this paper,we make full use of the summation method within the ordered product of operators and the generating function formula for two-variable Hermite polynomials. 相似文献
87.
A generalized Weyl—Wigner quantization scheme unifying P-Q and Q-P ordering and Weyl ordering of operators 下载免费PDF全文
By extending the usual Wigner operator to the s-parameterized one as 1/4π2 integral (dyduexp [iu(q-Q)+iy(p-P)+is/2yu]) from n=- ∞ to ∞ with s beng a,real parameter,we propose a generalized Weyl quantization scheme which accompanies a new generalized s-parameterized ordering rule.This rule recovers P-Q ordering,Q-P ordering,and Weyl ordering of operators in s = 1,1,0 respectively.Hence it differs from the Cahill-Glaubers’ ordering rule which unifies normal ordering,antinormal ordering,and Weyl ordering.We also show that in this scheme the s-parameter plays the role of correlation between two quadratures Q and P.The formula that can rearrange a given operator into its new s-parameterized ordering is presented. 相似文献
88.
Based on the newly developed coherent-entangled state representation,we propose the so-called Fresnel-Weyl complementary transformation operator.The new operator plays the roles of both Fresnel transformation(for(a 1 a 2)/√ 2) and the Weyl transformation(for(a 1 + a 2)/√ 2).Physically,(a 1 a 2)/√ 2 and(a 1 + a 2)/√ 2 could be a symmetric beamsplitter’s two output fields for the incoming fields a 1 and a 2.We show that the two transformations are concisely expressed in the coherent-entangled state representation as a projective operator in the integration form. 相似文献
89.
Based on the Wigner operator in the entangled state representation we study some new important properties of Wigner function for bipartite entangled systems, such as size of an entangled state, upper bound of Wigner functions, etc. These discussions demonstrate the beauty and elegance of the entangled state representation. 相似文献
90.