共查询到20条相似文献,搜索用时 15 毫秒
1.
A new bipartite coherent-entangled state (CES) is found which exhibits both coherent state and entangled state properties. The set of CESs constitute a complete and partly nonorthogonal representation. Using an asymmetric beamsplitter a experimental scheme to produce the CES is proposed. Applications of CESs in quantum optics are also presented. 相似文献
2.
Xiang-Guo Meng Ji-Suo Wang Bao-Long Liang 《International Journal of Theoretical Physics》2011,50(3):906-915
A new kind of bipartite coherent-entangled state (CES) is introduced in the two-mode Fock space which exhibits the properties
of both coherent state and entangled state. The set of CESs make up a complete and partly nonorthogonal representation. A
simple experimental scheme to produce the CES is proposed by using a beam splitter. Some applications of the CES are also
presented in quantum optics. 相似文献
3.
《声学学报:英文版》2017,(1)
Coded excitation technology(CET) can effectively enhance the penetration and resolution of ultrasonic testing.To analyze the influence of rock properties on pulse compression performance(PCP) of coded excitation signals(CES),a numerical simulation,and an ultrasonic experiment on different rock samples are performed;and the detection ability of several CESs are also investigated and compared.The results of experiments showed that the loss of the signal-to-noise ratio(SNR) of Barker coded signal with tapered linear frequency modulated carrier(BTLFM) is always less than Barker coded signal with sine carrier(BS),while the resolution loss of BTLFM is lower than tapered linear frequency modulated signal(TLFM).In sum,the results not only verifiy the effectiveness of CET,but also provide a basis for the parameter settings of coded signals used in rock ultrasonic testing. 相似文献
4.
FAN Hong-Yi WANG Wen-Qin 《理论物理通讯》2006,46(6):975-982
We introduce the new concept of coherent-entangled state (CES). By virtue of the technique of integration within an ordered product of operators we introduce a new kind of three-mode CES [β,γ,x), which exhibits both properties of the coherent state and the entangled state. [β,γ,x) makes up a new quantum mechancial representation. Its applications in quantum optics are also presented. 相似文献
5.
We introduce the so-called coherent-entangled state
(CES) in the four-mode Fock space, which makes up a new quantum
mechanical representation owing to completeness relation and
orthogonal property. Its standard Schmidt decomposition and
experimental generation using beam-splitter (BS) are proposed. In
addition, its applications in quantum optics are presented. Finally,
we extend it to multi-mode case and discuss some applications, too. 相似文献
6.
FAN Hong-Yi WANG Wen-Qin 《理论物理通讯》2006,46(12)
We introduce the new concept of coherent-entangled state (CES). By virtue of the technique of integration Its applications in quantum optics are also presented. 相似文献
7.
L. V. Lutsev M. N. Kopytin A. V. Sitnikov O. V. Stognei 《Physics of the Solid State》2005,47(11):2169-2179
The electrical resistance of granular structures with ferromagnetic and nonferromagnetic metal nanoparticles embedded in concentrations below the percolation threshold was studied in strong electric fields. More specifically, amorphous silicon dioxide containing nanoparticles of a Co41Fe39B20 alloy [(a-SiO2)100? x(Co41Fe39B20)x structure] and amorphous hydrogenated carbon with embedded copper nanoparticles, a-C: H(Cu), were investigated. The (a-SiO2)100?x(Co41Fe39B20)x structures revealed changes in the electrical resistance and magnetoresistance after being subjected to a strong electric field. The changes could have reversible or irreversible character and depended on the electrical prehistory of the sample. A strong electric field caused not only a decrease in the electrical resistance but also a decrease in the magnetoresistance, although the magnetization of the sample remained unchanged. The temperature dependences of the current in a-C: H(Cu) films exhibited conductivity peaks under a decrease in temperature in strong electric fields and transitions from the insulating to conducting state; after the field was removed, there occurred reverse transitions and conductivity relaxation, as well as pronounced changes in the dielectric permittivity and an increase in dielectric losses with increasing temperature. A model of cluster electronic states (CESs) is proposed to account for the experimental findings. These states are created by electrons of the metal grains and matrix defects near the Fermi surface. The observed features find explanation in a change in the CES structure. A strong electric field does not bring about d-electron delocalization, and the fraction of d electron wave functions in a CES is small. 相似文献
8.
LI Heng-Mei YUAN Hong-Chun 《理论物理通讯》2008,50(11):1081-1088
We introduce the so-called coherent-entangled state (CES) in the four-mode Fock space, which makes up a new quantum mechanical representation owing to completeness relation and orthogonal property. Its standard Schmidt decomposition and experimental generation using beam-splitter (BS) are proposed. In addition, its applications in quantum optics are presented. Finally, we extend it to multi-mode case and discuss some applications, too. 相似文献
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10.
柱状磁光颗粒的局域表面等离激元共振为二维磁光光子晶体的手征性边缘模的生成提供了重要的机制. 但目前对此类颗粒的局域表面等离激元共振效应的研究局限于长波长近似下的结果, 且缺乏对发生共振时的远场与近场特征的深入了解. 本文从散射理论出发, 计算并分析了柱状磁光颗粒发生局域表面等离激元共振的条件与特殊的场特征, 并讨论了颗粒尺寸对共振峰的影响. 计算结果解释了实验中观察到的二维磁光光子晶体的共振带隙与在长波长近似下得到的局域表面等离激元共振频率的明显偏移, 并展示了颗粒在较大尺寸下形成的高阶共振峰, 这可能有助于利用共振效应在磁光光子晶体中实现多模的手征边缘态. 相似文献
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12.
对高温高压下惰性等离子体的电离度和物态方程,给出了一种基于Thomas-Feimi(TF)统计模型的简化计算新方法,即首先对TF模型电离势的数值结果进行函数逼近,得出近似计算电离势的简单解析函数;在局部热动平衡情况下,假定离子数密度n(Z*)为Z*的连续函数,再由Debye-Hückel修正的 Saha 方程,得出了一个便于数值求解的电离度的近似计算公式,从而建立了一种惰性等离子体物态方程的简化模型,并对氦、氖、氩三种惰性物质等离子体进行了计算.计算结果与其他文献计算结果和实验值均符合很好.所提出的简单模型也适用于计算混合物物态方程,在高温高密度强电离等离子体领域将有更为广阔的应用前景. 相似文献
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14.
L. Santos M. Lewenstein 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,7(3):379-390
We study a dynamical scheme for condensation of bosonic trapped gases beyond the Lamb-Dicke limit, when the photon-recoil
energy is larger than the energy spacing of the trap. Using quantum master equation formalism we demonstrate that dark-state
cooling methods similar to those designed for a single trapped atom allow for the condensation of a collection of bosons into
a single state of the trap, either the ground, or an excited state. By means of Monte-Carlo simulations we analyse the condensation
dynamics for different dimensions, and for different cooling schemes.
Received 30 November 1998 and Received in final form 20 March 1999 相似文献
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16.
She-Sheng Xue 《General Relativity and Gravitation》2006,38(7):1135-1172
We study a possible gravitational vacuum-effect, in which vacuum-energy variation is due to variation of gravitational field, vacuum state gains gravitational energy and releases it by spontaneous photon emissions. Based on the path-integral representation, we present a general formulation of vacuum transition matrix and energy-momentum tensor of a quantum scalar field theory in curved spacetime. Using analytical continuation of dimensionality of the phase space, we calculate the difference of vacuum-energy densities in the presence and absence of gravitational field. Using the dynamical equation of gravitational collapse, we compute the rate of vacuum state gaining gravitational energy. Computing the transition amplitude from initial vacuum state to final vacuum state in gravitational collapsing process, we show the rate and spectrum of spontaneous photon emissions for releasing gravitational energy. We compare our idea with the Schwinger idea for Sonoluminiescence and contrast our scenario with the Hawking effect. 相似文献
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18.
Quantum Statistic Entropy of Three-Dimensional BTZ Black Hole 总被引:1,自引:0,他引:1
Using the new equation of state density motivated by the generalized uncertainty relation in the quantum gravity, we investigate entropy of a black line on the background of the three-dimensional BTZ. In our calculation, we need not introduce cutoff and can remove the divergent term in the original brick-wall method via the new equation of state density. And it is obtained that the entropy of the black line is proportional to the area of the horizon (perimeter). Further it is shown the entropy of black line is the entropy of quantum state on the surface of horizon (perimeter). The black line entropy is the intrinsic property of the black hole. The entropy is a quantum effect. By using quantum statistical method, we directly obtain the partition function of Bose field and fermi field on the background of the black line. The difficulty to solve wave equation of various particles is avoided. We offer a new simple and direct way for calculating the entropy of various spacetime black holes (black plane, black line and black column).
PACS 04.20.Dw; 97.60.Lf 相似文献
19.
利用费米相干态和正规乘积内的积分法,研究费米体系下两个态的交换算符.得到了交换算符在相干态表象中和粒子数表象中的表示,同时将其推广到在多状态情况下态之间的循环交换. 相似文献
20.
This paper undertakes a nonlinear analysis of a model for a maglev system with time-delayed feedback. Using linear analysis, we determine constraints on the feedback control gains and the time delay which ensure stability of the maglev system. We then show that a Hopf bifurcation occurs at the linear stability boundary. To gain insight into the periodic motion which arises from the Hopf bifurcation, we use the method of multiple scales on the nonlinear model. This analysis shows that for practical operating ranges, the maglev system undergoes both subcritical and supercritical bifurcations, which give rise to unstable and stable limit cycles respectively. Numerical simulations confirm the theoretical results and indicate that unstable limit cycles may coexist with the stable equilibrium state. This means that large enough perturbations may cause instability in the system even if the feedback gains are such that the linear theory predicts that the equilibrium state is stable. 相似文献