English
Related papers

Related papers: Entanglement types for two-qubit states with real …

200 papers

The existence of a maximally entangled pure state is a cornerstone result of entanglement theory that has paramount consequences in quantum information theory. A natural generalization of this property is to consider whether a notion of…

Quantum Physics · Physics 2026-02-12 Gonzalo Camacho , Julio I. de Vicente

Entanglement for pure bipartite states is most commonly quantified in a state-by-state manner to each pure state of a bipartite system a scalar quantity, such as the von Neumann entropy of a reduced density matrix. This provides a precise…

Quantum Physics · Physics 2025-11-27 Loris Di Cairano

In a $d$-dimensional topological insulator of order $d$, there are zero energy states on its corners which have close relationship with its entanglement behaviors. We studied the bipartite entanglement spectra for different subsystem shapes…

Mesoscale and Nanoscale Physics · Physics 2019-07-04 Qiang Wang , Da Wang , Qiang-Hua Wang

Consider a ring of N qubits in a translationally invariant quantum state. We ask to what extent each pair of nearest neighbors can be entangled. Under certain assumptions about the form of the state, we find a formula for the maximum…

Quantum Physics · Physics 2009-11-06 Kevin M. O'Connor , William K. Wootters

We in this paper strictly prove that some block diagonalizable two qubit entangled state with six none zero elements reaches its quantum relative entropy entanglement by the a separable state having the same matrix structure. The entangled…

Quantum Physics · Physics 2009-11-11 Xiao-yu Chen , Li-min Meng , Li-zhen Jiang , Xiang-jun Li

Strong numerical evidence is presented suggesting that all two-qubit mixed states are equivalent to X states by a single entanglement-preserving unitary (EPU) transformation, so that the concurrence of such an X state equals that of the…

Quantum Physics · Physics 2014-08-11 Samuel R. Hedemann

We discuss the construction of $n$-qubit pure states with maximum bipartite entanglement across all possible choices of $k$ vs $n-k$ bi-partitioning, which implies that the Von Neumann entropy of every $k$-qubit reduced density matrix…

Quantum Physics · Physics 2022-07-26 Sowrabh Sudevan , Sourin Das

The classification of multipartite entanglement is essential as it serves as a resource for various quantum information processing tasks. This study concerns a particular class of highly entangled multipartite states, the so-called…

Quantum Physics · Physics 2024-11-07 N Ramadas , Arul Lakshminarayan

A general method in constructing a complete set of wave functions for multipartite identical qubits is presented based on the irreducible representations of the permutation group and the nth rank tensors. Particular examples for n =2, 3,…

Quantum Physics · Physics 2007-05-23 P. J. Lin-Chung

We propose novel mixed states in two qubits, ``maximally entangled mixed states'', which have a property that the amount of entanglement of these states cannot be increased further by applying any unitary operations. The property is proven…

Quantum Physics · Physics 2007-05-23 Satoshi Ishizaka , Tohya Hiroshima

A nice and interesting property of any pure tensor-product state is that each such state has distillable entangled states at an arbitrarily small distance $\epsilon$ in its neighborhood. We say that such nearby states are…

Quantum Physics · Physics 2017-01-27 Michel Boyer , Aharon Brodutch , Tal Mor

The familiar Greenberger-Horne-Zeilinger (GHZ) states can be rewritten by entangling the Bell states for two qubits with a state of the third qubit, which is dubbed entangled entanglement. We show that in this way we obtain all 8…

Quantum Physics · Physics 2015-10-06 Gabriele Uchida , Reinhold A. Bertlmann , Beatrix C. Hiesmayr

The geometric measure of entanglement of a pure quantum state is defined to be its distance to the space of product (seperable) states. Given an $n$-partite system composed of subsystems of dimensions $d_1,\ldots, d_n$, an upper bound for…

Quantum Physics · Physics 2018-05-09 Liqun Qi , Guofeng Zhang , Guyan Ni

Generation of entangled state is of paramount importance both from quantum theoretical foundation and technology applications. Entanglement swapping provides an efficient method to generate entanglement in quantum communication protocols.…

Quantum Physics · Physics 2020-11-05 Meng Li , Yun Shang

In this paper we study the production of entanglement between two atoms which are far from each other. We consider a system including eight two-level atoms (1; 2;... ; 8) such that any atom with its adjacent atom is in atomic Bell state, so…

Quantum Physics · Physics 2021-06-04 M Ghasemi , M K Tavassoly

The geometric measure of entanglement is the distance or angle between an entangled target state and the nearest unentangled state. Often one considers the geometric measure of entanglement for highly symmetric entangled states because it…

Quantum Physics · Physics 2015-12-14 M. E. Carrington , G. Kunstatter , J. Perron , S. Plosker

Entanglement in a class of bipartite generalized coherent states is discussed. It is shown that a positive parameter can be associated with the bipartite generalized coherent states so that the states with equal value for the parameter are…

Quantum Physics · Physics 2009-11-13 S. Sivakumar

In [Science 340, 1205, 7 June (2013)], via polytopes Michael Walter et al. proposed a sufficient condition detecting the genuinely entangled pure states. In this paper, assume that a state with six non-zero coefficients is not a trivially…

Quantum Physics · Physics 2025-10-21 Dafa Li

Using the natural connection equivalent to the SU(2) Yang-Mills instanton on the quaternionic Hopf fibration of $S^7$ over the quaternionic projective space ${\bf HP}^1\simeq S^4$ with an $SU(2)\simeq S^3$ fiber the geometry of entanglement…

Quantum Physics · Physics 2008-11-26 Peter Levay

Geometric properties of the set of quantum entangled states are investigated. We propose an explicit method to compute the dimension of local orbits for any mixed state of the general K x M problem and characterize the set of effectively…

Quantum Physics · Physics 2009-11-06 Marek Kus , Karol Zyczkowski