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Related papers: Different classes of quantum gates entanglers

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In quantum networks, one way to communicate is to distribute entanglements through swapping at intermediate nodes. Most existing work primarily aims to create efficient two-party end-to-end entanglement over long distances. However, some…

We find that a bipartite quantum state is entangled if and only if it is quantum coherent with respect to complete bases of states in the corresponding system that are distinguishable under local quantum operations and classical…

Quantum Physics · Physics 2022-01-19 Asmitha Mekala , Ujjwal Sen

We construct a class of entangled states in $\mathcal{H}=\mathcal{H}_{A}\otimes\mathcal{H}_{B}\otimes\mathcal{H}_{C}$ quantum systems with $dim\mathcal{H}_{A}=dim\mathcal{H}_{B}=dim\mathcal{H}_{C}=2$ and classify those states with respect…

Quantum Physics · Physics 2015-09-25 Hui Zhao , Xinyu Yu , Naihuan Jing

The formation of multipartite quantum entanglement by repeated operation of one and two qubit gates is examined. The resulting entanglement is evaluated using two measures: the average bipartite entanglement and the Groverian measure. A…

Quantum Physics · Physics 2009-11-13 Yonatan Most , Yishai Shimoni , Ofer Biham

Large number of multimode entangled states of light generated in down conversion processes belongs to a collection which is natural generalization of the W class. A brief overview of these states, schemes for their preparation, experimental…

Quantum Physics · Physics 2007-05-23 V. N. Gorbachev , A. I. Trubilko

A scheme for generating an entangled state in a two spin-1/2 system by means of a spin-dependent potential scattering of another qubit is presented and analyzed in three dimensions. The entanglement is evaluated in terms of the concurrence…

Quantum Physics · Physics 2010-04-07 Yuichiro Hida , Hiromichi Nakazato , Kazuya Yuasa , Yasser Omar

In this paper we consider a system consist of a qubit and a qutrit, and find a formula to evaluate the concurrence for it. We show that entanglement of formation for this system obeys the same relation as for two-qubits.

Quantum Physics · Physics 2007-05-23 Safa Jami , Mohsen Sarbishei

Entanglement in high-dimensional many-body systems plays an increasingly vital role in the foundations and applications of quantum physics. In the present paper, we introduce a theoretical concept which allows to categorize multipartite…

Quantum Physics · Physics 2012-12-27 Christoph Spengler , Marcus Huber , Andreas Gabriel , Beatrix C. Hiesmayr

A gate is called entangler if it transforms some (pure) product states to entangled states. A universal entangler is a gate which transforms all product states to entangled states. In practice, a universal entangler is a very powerful…

Quantum Physics · Physics 2009-11-13 Jianxin Chen , Runyao Duan , Zhengfeng Ji , Mingsheng Ying , Jun Yu

We introduce a class of mixed multiqubit states, that corresponds to a randomized version of graph states. Such states arise when a graph state is prepared with noisy or imperfect controlled-Z gates. We study the entanglement features of…

Given a finite group G with a bilocal representation, we investigate the bipartite entanglement in the state constructed from the group algebra of G acting on a separable reference state. We find an upper bound for the von Neumann entropy…

Quantum Physics · Physics 2007-05-23 Alioscia Hamma , Radu Ionicioiu , Paolo Zanardi

We propose a deterministic scheme of generating genuine multiparty entangled states in quantum networks of arbitrary size having various geometric structures -- we refer to it as entanglement circulation. The procedure involves optimization…

Quantum Physics · Physics 2022-09-16 Pritam Halder , Ratul Banerjee , Srijon Ghosh , Amit Kumar Pal , Aditi Sen De

Certain quantum gates, such as the controlled-NOT gate, are symmetric in terms of the operation of the control system upon the target system and vice versa. However, no operational criteria yet exist for establishing whether or not a given…

Quantum Physics · Physics 2009-11-07 John A. Vaccaro , O. Steuernagel , S. F. Huelga

We present a class of maximally entangled states generated by a high-dimensional generalisation of the \textsc{cnot} gate. The advantage of our approach is the simple algebraic structure of both entangling operator and resulting entangled…

Quantum Physics · Physics 2015-09-22 Anna Chiara Lai , Marco Pedicini , Silvia Rognone

We investigate the entanglement properties of multiparticle systems, concentrating on the case where the entanglement is robust against disposal of particles. Two qubits -belonging to a multipartite system- are entangled in this sense iff…

Quantum Physics · Physics 2009-11-06 W. Dür

Multipartite quantum states may exhibit different types of quantum entanglement in that they cannot be converted into each other by local quantum operations only, and fully understanding mathematical structures of different types of…

Quantum Physics · Physics 2020-06-24 Lijinzhi Lin , Zhaohui Wei

Unitary gates with high entangling capabilities are relevant for several quantum-enhanced technologies. For symmetric multiqubit systems, such as spin states or bosonic systems, the particle exchange symmetry restricts these gates and also…

We provide a complete analysis of mixed three-qubit states composed of a GHZ state and a W state orthogonal to the former. We present optimal decompositions and convex roofs for the three-tangle. Further, we provide an analytical method to…

Quantum Physics · Physics 2007-05-23 Robert Lohmayer , Andreas Osterloh , Jens Siewert , Armin Uhlmann

We assess quantum non-locality of multiparty entangled thermal states by studying, quantitatively, both tripartite and quadripartite states belonging to the Greenberger-Horne-Zeilinger (GHZ), W and linear cluster-state classes and showing…

Quantum Physics · Physics 2015-05-18 G. McKeown , F. L. Semiao , H. Jeong , M. Paternostro

We examine a simple scheme to generate genuine multipartite entangled states across disjoint qubit registers. We employ a shuttle qubit that is sequentially coupled, in an energy preserving manner, to the constituents within each register…