共查询到20条相似文献,搜索用时 15 毫秒
1.
In this work, we investigate the feasibility of teleporting an unknown qudit with unit fidelity and non-unit probability using partially entangled state as a shared resource. We also give an expression for the probability of success for teleportation of an unknown qudit. 相似文献
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C. J. Happ M. Freyberger 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,64(2-3):579-583
We present a strategy for estimation of d-level quantum states and for the simple adaption of corresponding measurements. The adaption method is inspired by mutually unbiased measurements, but it is also applicable in cases for which no complete set of mutually unbiased bases is known. We present results of Monte Carlo simulations, that demonstrate the fidelity gain of the adaptive strategy compared to a non-adaptive estimation. 相似文献
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廖湘萍等(Chin.Phys.B 23 020304,2014)指出弱测量和弱测量反转操作可以保护三个量子比特的纠缠,提高保真度.本文将弱测量方法推广至四个量子比特的情况,研究了几种典型四个量子比特量子态的演化.结果表明:在振幅阻尼通道中,弱测量方法能够有效地提高系统量子态的保真度.分析了影响量子态保真度的各种因素,对比了不同量子态的演化特征,划分了量子态保真度提高的敏感区域.最后,对弱测量方法抑制量子态衰减的内在机制做了合理的物理解释. 相似文献
4.
《中国物理 B》2019,(8)
In this paper, we propose a new approach to tackle the separability problem for bipartite qudit mixed-states. This is based on the Majorana representation which allows to represent a N-spinors(qudit) as a symmetric state of N spin-1/2. We also discuss how we can exploit such representation and the notion of the biseparability of multipartite qubit states in the sense to establish new criteria of the separability problem based on the PPT and concurrence. 相似文献
5.
A linear map of qudit tomogram onto qubit tomogram (qubit portrait) is proposed as a characteristics of the qudit state. In
view of the qubit-portrait method, the Bell inequalities for two qubits and two qutrits are discussed within the framework
of the probability-representation of quantum mechanics. A semigroup of stochastic matrices is associated with tomographic-probability
distributions of qubit and qutrit states. Bell-like inequalities are studied using the semigroup of stochastic matrices. The
qudit-qubit map of tomographic probability distributions is discussed as an ansatz to provide a necessary condition for the
separability of quantum states. 相似文献
6.
We investigate the problem of teleportation of an M-qubit state by using an entangled qudit pair as a quantum channel and show that the teleportation of a multiparticle state can correspond to the teleportation of a multi-dimensional state. We also introduce a quantum-state converter composed of beamsplitter arrays, on/off-detectors and cross-Kerr couplers and demonstrate that the state conversion from an M-qubit to an N-dimensional qudit and vice versa can be implemented with this converter, where N=2^M. Based on this, an experimentally feasible scheme for the teleportation of an M-qubit via an entangled N-level qudit pair channel is proposed. 相似文献
7.
We present a tripartite quantum information splitting scheme which splits a qutrit state via two GHZ states. The scheme is then generalized to splitting a qudit state among any number of receivers. We show that this scheme is also applicable to splitting any multi-qudit entangled states. 相似文献
8.
We discuss some inequalities for N nonnegative numbers. We use these inequalities to obtain known inequalities for probability distributions and new entropic and information inequalities for quantum tomograms of qudit states. The inequalities characterize the degree of quantum correlations in addition to noncontextuality and quantum discord. We use the subadditivity and strong subadditivity conditions for qudit tomographic-probability distributions depending on the unitary-group parameters in order to derive new inequalities for Shannon, Rényi, and Tsallis entropies of spin states. 相似文献
9.
《Physics letters. A》2003,311(6):459-464
In this Letter, we consider the optimal probabilistic teleportation in N-level qudit via information extraction. We also argue that the purification scheme via entanglement swapping cannot achieve optimal efficiency in N-qubit case when N is larger than 2. 相似文献
10.
Stochastic and bistochastic matrices providing positive maps for spin states (for qudits) are shown to form semigroups with dense intersection with the Lie groups IGL(n,R) and GL(n,R) respectively. The density matrix of a qudit state is shown to be described by a spin tomogram determined by an orbit of the bistochastic semigroup acting on a simplex. A class of positive maps acting transitively on quantum states is introduced by relating stochastic and quantum stochastic maps in the tomographic setting. Finally, the entangled states of two qubits and Bell inequalities are given in the framework of the tomographic probability representation using the stochastic semigroup properties. 相似文献
11.
In this paper we define homological stabilizer codes on qubits which encompass codes such as Kitaev’s toric code and the topological color codes. These codes are defined solely by the graphs they reside on. This feature allows us to use properties of topological graph theory to determine the graphs which are suitable as homological stabilizer codes. We then show that all toric codes are equivalent to homological stabilizer codes on 4-valent graphs. We show that the topological color codes and toric codes correspond to two distinct classes of graphs. We define the notion of label set equivalencies and show that under a small set of constraints the only homological stabilizer codes without local logical operators are equivalent to Kitaev’s toric code or to the topological color codes. 相似文献
12.
基于一种特殊的控制非门,实现多光子偏振态与单光子空间高维态之间的相互变换,使得对多光子偏振态的操作可以通过对单光子的操作来完成,由此可以实现任意多光子正定算符值测量和多光子任意幺正操作.这种实现方式是以一定概率完成的,但其效率要优于此前的方案,在目前的实验条件下是可行的.
关键词:
单光子空间态
特殊控制非门
线性光学多端口干涉仪 相似文献
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14.
Quantum state sharing of an arbitrary qudit state by using nonmaximally generalized GHZ state 下载免费PDF全文
We present a scheme for quantum state sharing of an arbitrary qudit state by using nonmaximally entangled generalized Greenberger-Horne-Zeilinger (GHZ) states as the quantum channel and generalized Bell-basis states as the joint measurement basis. We show that the probability of successful sharing an unknown qudit state depends on the joint measurements chosen by Alice. We also give an expression for the maximally probability of this scheme. 相似文献
15.
We address the problem of encoding entanglement-assisted (EA) quantum error-correcting codes (QECCs) and of the corresponding complexity. We present an iterative algorithm from which a quantum circuit composed of CNOT, H, and S gates can be derived directly with complexity O(n2) to encode the qubits being sent. Moreover, we derive the number of each gate consumed in our algorithm according to which we can design EA QECCs with low encoding complexity. Another advantage brought by our algorithm is the easiness and efficiency of programming on classical computers. 相似文献
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In this letter, we proposed a new family of graphical quantum stabilizer codes (QSCs) based on block Jacket transform and
its fast construction approach. The approach provides great flexibility in designing a stabilizer with a large block length
and a high efficiency in terms of recursive relations. According to the graph theory, the present quantum code construction
method has a low coding complexity and the codes are asymptotically good. 相似文献
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