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1.
There are practical motivations to construct genuine tripartite entangled states based on the collective use of two bipartite entangled states. Here, the case that the states are two‐qubit Werner states is considered. The intervals of parameters of two‐qubit Werner states are revealed such that the tripartite state is genuinely entangled. Furthermore, we also investigate the lower bound of genuine multipartite entanglement concurrence for tripartite qudit states. Several examples are given to show the effectiveness of the lower bound. 相似文献
2.
YU Chang-Shui WANG Ya-Hong SONG He-Shan 《理论物理通讯》2007,47(6):1041-1044
In this paper, we propose a protocol to deterministically teleport an unknown mixed state of qubit by utilizing a maximally bipartite entangled state of qubits as quantum channel. Ira non-maximally entangled bipartite pure state is employed as quantum channel, the unknown mixed quantum state of qubit can be teleported with 1 -√ 1- C^2 probability, where C is the concurrence of the quantum channel. The protocol can also be generalized to teleport a mixed state of qudit or a multipartite mixed state. More important purpose is that, on the basis of the protocol, the teleportation of an arbitrary multipartite (pure or mixed) quantum state can be decomposed into the teleportation of each subsystem by employing separate entangled states as quantum channels. In the case of deterministic teleportation, Bob only needs to perform unitary transformations on his single particles in order to recover the initial teleported multipartite quantum state. 相似文献
3.
二粒子部分缠结态的量子隐形传态 总被引:2,自引:1,他引:1
利用三粒子的最大缠结态(即GHZ态)作为量子通道,实现二粒子部分缠结态的隐形传态,其成功几率为1.该方案只需借助一个量子比特作为辅助比特和两次贝尔基测量,其操作均为局域操作且在目前技术条件下可以很容易实现. 相似文献
4.
《Physics letters. A》2014,378(30-31):2074-2078
In this paper, we propose a method to generate multipartite entangled coherent states (MECS) using a multi-mode superconducting cavity containing an SQUID-based charge qubit. After the projective measurement of simple charge states, MECS representing nonlocal electromagnetic fields of cavity modes have been generated. Furthermore, we investigate the nonlocal properties of the generated MECS by constructing the new concurrence-like entanglement based on the Bell–Klyshko argument. 相似文献
5.
Multiparty quantum secret conference based on quantum encryption with pure entangled states 下载免费PDF全文
We present a scheme for multiparty quantum remote secret conference
(MQRSC) with pure entangled states, not maximally entangled
multipartite quantum systems. The conferees first share a private
quantum key, a sequence of pure entangled states and then use them
to encode and decode the secret messages. The conferees exploit the
decoy-photon technique to ensure the security of the transmission of
qubits. This MQRSC scheme is more feasible and efficient than
others. 相似文献
6.
L. B. Yu Z.-Y. Xue Z. D. Wang Y. Yu S. L. Zhu 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2011,61(2):499-505
The interaction between a superconducting phase qubit and
the two-level systems located inside the Josephson tunnel barrier
is described by the XY model, which is naturally used to
implement the i-SWAP gate. With this gate, we propose a scheme to
efficiently generate multi-qubit entangled states of such
two-level systems, including multipartite W state and cluster
states. In particular, it is found that, with the help of the phase
qubit, the entanglement witness can be used to efficiently detect
the produced multi-qubit entangled states. 相似文献
7.
Kui Hou Jing Wang Yi-Lin Lu Shou-Hua Shi 《International Journal of Theoretical Physics》2009,48(7):2005-2015
For two parties sharing the original state, a scheme for remote preparation of the two-particle entangled state by three partial
two-particle entangled states as the quantum channel is presented, and then directly generalize the scheme for remotely preparing
a multipartite GHZ-class state for M senders. It is shown that the receiver can obtain the unknown state with certain probability under the condition that only
and only if all the senders collaborate with each other. The N-particle projective measurement and the von Neumann measurement are needed in our scheme. The probability of the successful
remote state preparation and classical communication cost are calculated. 相似文献
8.
We study the Bell's inequality and multipartite entanglement generation for initially maximally entangled states of free Dirac field in a non inertial frame and asymptotically flat Robertson–Walker space-time.For two qubit case,we show that the Bell's inequality always is violated as measured by the accelerated observers which are in the causally connected regions.On the other hand,for those observers in the causally disconnected regions inequality is not violated for any values of acceleration.The generated three qubit state from two qubit state due to acceleration of one parties has a zero 3-tangle.For a three qubit state,the inequality violated for measurements done by both causally connected and disconnected observers.Initially GHZ state with non zero 3-tangle,in accelerated frame,transformed to a four qubit state with vanishing 4-tangle value.On the other hand,for a W-state with zero 3-tangle,in non inertial frame,transformed to a four qubit state with a non-zero 4-tangle acceleration dependent.In an expanding space-time with asymptotically flat regions,for an initially maximally entangled state,the maximum value of violation of Bell's inequality in the far past decreased in the far future due to cosmological particle creation.For some initially maximally entangled states,the generated four qubit state due to expansion of space-time,has non vanishing 4-tangle. 相似文献
9.
Tong Liu Bao-Qing Guo Yan-Hui Zhou Jun-Long Zhao Yu-Liang Fang Qi-Cheng Wu Chui-Ping Yang 《Frontiers of Physics》2022,17(6):61502
Transferring entangled states between matter qubits and microwave-field (or optical-field) qubits is of fundamental interest in quantum mechanics and necessary in hybrid quantum information processing and quantum communication. We here propose a way for transferring entangled states between superconducting qubits (matter qubits) and microwave-field qubits. This proposal is realized by a system consisting of multiple superconducting qutrits and microwave cavities. Here, „qutrit” refers to a three-level quantum system with the two lowest levels encoding a qubit while the third level acting as an auxiliary state. In contrast, the microwave-field qubits are encoded with coherent states of microwave cavities. Because the third energy level of each qutrit is not populated during the operation, decoherence from the higher energy levels is greatly suppressed. The entangled states can be deterministically transferred because measurement on the states is not needed. The operation time is independent of the number of superconducting qubits or microwave-field qubits. In addition, the architecture of the circuit system is quite simple because only a coupler qutrit and an auxiliary cavity are required. As an example, our numerical simulations show that high-fidelity transfer of entangled states from two superconducting qubits to two microwave-field qubits is feasible with present circuit QED technology. This proposal is quite general and can be extended to transfer entangled states between other matter qubits (e.g., atoms, quantum dots, and NV centers) and microwave- or optical-field qubits encoded with coherent states. 相似文献
10.
Simple Entanglement Measure for Multipartite Pure States 总被引:3,自引:0,他引:3
Feng Pan Feng Pan Feng Pan Dan Liu Guoying Lu J. P. Draayer 《International Journal of Theoretical Physics》2004,43(5):1241-1247
A simple entanglement measure for multipartite pure states is formulated based on the partial entropy of a series of reduced density matrices. Use of the proposed new measure to distinguish disentangled, partially entangled, and maximally entangled multipartite pure states is illustrated. 相似文献
11.
12.
The preparation of multipartite entangled states is the prerequisite for exploring quantum information networks and quantum computation.In this paper,we review the experimental progress in the preparation of cluster states and multi-color entangled states with continuous variables.The preparation of lager scale multipartite entangled state provide valuable quantum resources to implement more complex quantum informational tasks. 相似文献
13.
We deduce entangled fractional Fourier transformation (EFFT) for
the multipartite entangled state representation, which was newly
constructed with two mutually conjugate n-mode entangled states of
continuum variables in n-mode Fock space. We establish a formalism
of EFFT for quantum mechanical wave functions, which provides
us a convenient way to derive some wave functions. We find that
the eigenmode of EFFT is different from the usual Hermite Polynomials.
We also derive the EFFT of the n-mode squeezed state. 相似文献
14.
We propose the methods of generating multipartite entanglement by considering the interaction of a system of N two-level atoms in M cavities of high quality factor with a strong classical driving field. It is shown that, with the cavity detuning, the applied driving field detuning and vacuum Rabi coupling, we can produce an entangled coherent state in two single-mode cavities and generate the entangled coherent cluster states in two bimodal vacuum cavities. Tuning these parameters also allows us to acquire the anti-Jaynes-Cummings (AJC) interaction, with which we can generate the maximally two-photon entangled states, and the two-atom and the two-photon entangled cluster states. 相似文献
15.
Characterization of the multipartite mixed state entanglement is still a challenging problem. This is due to the fact that the entanglement for the mixed states, in general, is defined by a convex-roof extension. That is the entanglement measure of a mixed state ρ of a quantum system can be defined as the minimum average entanglement of an ensemble of pure states. In this paper, we show that polynomial entanglement measures of degree 2 of even-N qubits X states is in the full agreement with the genuine multipartite (GM) concurrence. Then, we plot the hierarchy of entanglement classification for four qubit pure states and then using new invariants, we classify the four qubit pure states. We focus on the convex combination of the classes whose at most the one of the invariants is non-zero and find the relationship between entanglement measures consist of non-zero-invariant, GM concurrence and one-tangle. We show that in many entanglement classes of four qubit states, GM concurrence is equal to the square root of one-tangle. 相似文献
16.
We propose a method to prepare multipartite entangled states such as cluster states and graph states based on the cavity input-output process and single photon measurement. Two quantum gates, a controlled phase gate and a fusion gate between two atoms trapped in respective cavities, are proposed to prepare atomic cluster states and graph states with one and two dimensions. We also introduce a scheme that can generate an arbitrary multipartite photon duster state which uses two coherent states as a qubit basis. 相似文献
17.
利用拉曼型的Jaynes-Cummings模型传送两比特的未知原子态 总被引:6,自引:3,他引:3
实现量子态的隐形传送、尤其是多比特量子态的隐形传送在量子信息领域中有非常重要的作用,提出了一种隐形传送两比特未知原子态的方案,在此方案中,用两个两粒子纠缠态代替一个三粒子纠缠态作为量子信道,而且此方案可推广到隐形传送N比特的未知原子态。 相似文献
18.
Probabilistic teleportation scheme of two-mode entangled photon states by using linear optic element
XIANG Shao-hua 《原子与分子物理学报》2003,20(3):425-428
A scheme for teleporting two-mode entangled photon states with the successful probability 33.3% is Proposed. In the sehane, the tdeported qubit is two-mode photon entangled states, and two pairs of EPR pair are usedas quantum channel between a sender and a recciver. This procedure is achieved by using two 50/50 symmetric beam aplitters and four photon number detectors with the help of classical information. 相似文献
19.
Paolo Facchi, et al. [Phys. Rev. A77 (2008) 060304(R)] presented a maximally multipartite entangled state (MMES). Here, we give a criterion for the identification of maximally entangled four-qubit states. Using this criterion, we not only identify some existing maximally entangled four-qubit states in the literature, but also find several new maximally entangled four-qubit states as well. 相似文献
20.
Preparation of entangled squeezed states and quantification of their entanglement 总被引:3,自引:0,他引:3 下载免费PDF全文
We propose a scheme for generating bipartite and multipartite entangled squeezed states via the Jaynes-Cummings model with large detuning. Bipartite entanglement of these entangled states is quantified by the concurrence. We also use the N-tangle to compute multipartite entanglement of these multipartite entangled squeezed states. Finally we discuss two limiting cases which arise from r→∞ and r→0, in which the multipartite entangled squeezed state reduces correspondingly into an N-qubit Greenberger-Horne-Zeilinger state and an N-qubit W state. 相似文献