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1.
We address the problem of information completeness of quantum measurements in connection to quantum state tomography and with particular concern to quantum symplectic tomography. We put forward some non-trivial situations where informatively incomplete set of tomograms allows as well the state reconstruction provided to have some a priori information on the state or its dynamics. We then introduce a measure of information completeness and apply it to symplectic quantum tomograms. 相似文献
2.
We show that the completeness relation of the charged coherent state can be obtained by using the Mellin transformation and contour integration method. As a result, a modification of the completeness relation of the charged coherent state given by D. Bhaumik et al. (J. Phys. A: Math. Gen. 9 (1976) 1507) is presented. 相似文献
3.
Four-mode continuous-variables entangled state: generation from beam splitter, a parametric down-conversion and a polarizer 下载免费PDF全文
We introduce a new kind of four-mode continuous variable entangled
state in Fock space. The completeness relation and the partly
nonorthonormal property of such a state are proven. The scheme to
generate this state is presented by combining a symmetrical
beamsplitter, a parametric down-conversion and a polarizer. After
making a single-mode quadrature amplitude measurement, the remaining
three modes are kept in entanglement. And its applications are also
discussed. 相似文献
4.
由Wigner算符的完备性和Weyl对应,我们推导出一个能获得纯态密度算符的新等式。借助此公式,可以方便快捷的构造出量子力学中一些有用的新表象。 相似文献
5.
New equation for deriving pure state density operators by Weyl correspondence and Wigner operator 下载免费PDF全文
By virtue of the completeness of Wigner operator and Weyl
correspondence we construct a general equation for deriving pure
state density operators. Several important examples are considered
as the applications of this equation, which shows that our approach
is effective and convenient for deducing these entangled state
representations. 相似文献
6.
Finite-dimensional even and odd nonlinear pair coherent states and their some nonclassical properties 下载免费PDF全文
In this paper a new class of finite-dimensional even and odd nonlinear pair coherent states (EONLPCSs), which can be realized via operating the superposed evolution operators D±(τ) on the state |q, 0), is constructed, then their orthonormalized property, completeness relations and some nonclassical properties are discussed. It is shown that the finite-dimensional EONLPCSs possess normalization and completeness relations. Moreover, the finite-dimensional EONLPCSs exhibit remarkably different sub-Poissonian distributions and phase probability distributions for different values of parameters q, η and ξ. 相似文献
7.
E. Prugovečki 《International Journal of Theoretical Physics》1977,16(5):321-331
We present criteria for comparing measurements on a given system from the point of view of the information they provide. These criteria lead to a concept ofinformational completeness of a set of observables, which generalizes the conventional concept of completeness. The entropy of a state with respect to an arbitrary sample space of potential measurement outcomes is defined, and then studied in the context of configuration space and fuzzy stochastic phase space.Supported in part by the National Research Council of Canada. 相似文献
8.
《Physics letters. A》1996,222(6):440-450
The classification and completeness of Bethe states is undertaken for the spin 4 Fateev-Zamolodchikov model. This special case is of particular interest as the energy can be derived in a simple closed form even for lattices of arbitrary finite size. The excitation spectrum over the ferromagnetic ground state is also derived. 相似文献
9.
Using the MelJin inversion formulas we derive the weight function for constructing the completeness relation of the boson SU(3) charged and hypercharged coherent state. A suitable contour integration is selected for this derivation. 相似文献
10.
构造出了奇偶对相干态的指数形式, 并把奇偶对相干态推广至有限维Hilbert空间, 获得了有限维奇偶对相干态, 然后讨论了它们的正交归一完备性、反聚束效应和相位概率分布. 结果表明, 在此空间中奇偶对相干态具有归一完备性, 但不具有正交性. 借助于数值计算发现, 无论q取何值, 在参数|ξ|的不同取值范围内, 对于5维Hilbert空间中奇偶对相干态在模1和模2两个方向上均可呈现反聚束效应, 并且此双模光场的光子均是相关的. 而在7维Hilbert空间中,奇偶对相干态相位概率分
关键词:
有限维奇偶对相干态
反聚束效应
相位概率分布 相似文献
11.
A new methodology of statistical estimation of the quality of quantum measurement protocols is considered. The method is based
on studying the completeness, adequacy, and accuracy of quantum measurement protocols. The completeness is estimated on the
basis of considering a singular decomposition of a special matrix, which is constructed based on the measurement operators.
The estimate of adequacy supposes the presence of redundancy in the measurement protocol as compared to the minimally possible
number of measurements that are necessary for full reconstruction of a quantum state. The adequacy of quantum measurements
is estimated as the degree of how much the redundant statistical data agree with the laws of quantum theory. The accuracy
characteristics of the statistical reconstruction of arbitrary quantum states are studied based on the universal statistical
distribution for accuracy losses. Examples of applying the developed methods are presented for seven quantum protocols based
on the geometry of polyhedra with a high degree of symmetry. 相似文献
12.
FAN Hong-Yi 《理论物理通讯》2002,38(12)
In the context of the nonlinear coherent state (NLCS) theory we introduce the generalized Weyl orderingoperator formulation. The corresponding generalized Wigner operator turns out to be the Weyl ordered Dirac δ-operatorfunctions. The completeness relation of NLCS is recast into generalized Weyl ordering form. The relationship betweennormal ordering, antinormal ordering and the generalized Weyl ordering is established which constitute a self-consistenttheory for NLCS. 相似文献
13.
We present a convenient approach to finding multi-partite entangled state with continuum variables, which is the common eigenvectors of center-of-mass coordinate and mass-weighted relative momenta, by decomposing the normally ordered Gaussian-form operator expressing the completeness relation which is constructed by analyzing the eigenvector equations. The whole derivation is based on the technique of integration within an ordered product of operators. 相似文献
14.
15.
FANHong-Yi 《理论物理通讯》2002,38(6):729-732
In the context of the nonlinear coherent state(NLCS)theory we introduce the generalized weyl ordering operator formulation.The corresponding generalzied wigner operator turns out to be the Weyl ordered diracδ-operator functions.The completeness relation of NLCS is recast into generalized Weyl ordering form,The relationship between normal ordering,antinormal ordering and the generalized Weyl ordering is established which constitute a self-consistent theory for NLCS. 相似文献
16.
Our primary purpose of this work is to explicitly construct the general multipartite Einstein-Podolsky-Rosen (EPR) entangled state in multi-mode Fock space for a system with different masses of particles, which makes up a new quantum mechanical representation owing to completeness relation and orthogonal property. Its entanglement can be seen more clearly by analyzing its standard Schmidt decomposition. In addition, some applications of
the multipartite entanglement are proposed including deriving the
generalized Wigner operator and squeezing operator. 相似文献
17.
This paper constructs a new type of finite-dimensional thermal coherent states (FDTCS), which differs from the proceeding thermal coherent state in construction, as realisations of SU(2) Lie algebra. Using the technique of integration within an ordered product of operator, it investigates the orthonormality and completeness relation of the FDTCS. Based on the thermal Wigner operator in the thermal entangled state representation, the Wigner function of the FDTCS is obtained. The nonclassical properties of the FDTCS are discussed in terms of the negativity of its Wigner function. 相似文献
18.
For any unit vector in an inner product space S, we define a mapping on the system of all -closed subspaces of S, F(S), whose restriction on the system of all splitting subspaces of S, E(S), is always a finitely additive state. We show that S is complete iff at least one such mapping is a finitely additive state on F(S). Moreover, we give a completeness criterion via the existence of a regular finitely additive state on appropriate systems of subspaces. Finally, the result will be generalized to general inner product spaces. 相似文献
19.
References: 《理论物理通讯》2007,47(1):31-34
We present the continuous state vector of the total coordinate of multi-partlcle and the state vector of their total momentum, respectively, which possess completeness relation in multi-mode Fock space by virtue of the integration within an order product (IWOP) technique. We also calculate the transition from classical transformation of variables in the states to quantum unitary operator, deduce a new multi-mode squeezing operator, and discuss its squeezing effect. In progress, it indicates that the IWOP technique provides a convenient way to construct new representation in quantum mechanics. 相似文献