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Related papers: Entanglement, Mixedness, and Spin-Flip Symmetry in…

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We discuss maximum entangled states of quantum systems in terms of quantum fluctuations of all essential measurements responsible for manifestation of entanglement. Namely, we consider maximum entanglement as a property of states, for which…

Quantum Physics · Physics 2007-05-23 Alexander A. Klyachko , Alexander S. Shumovsky

One of the essential features of quantum mechanics is that most pairs of observables cannot be measured simultaneously. This phenomenon is most strongly manifested when observables are related to mutually unbiased bases. In this paper, we…

Quantum Physics · Physics 2015-05-27 M. Wiesniak , T. Paterek , A. Zeilinger

The present article proposes a measure of correlation for multiqubit mixed states. The measure is defined recursively, accumulating the correlation of the subspaces, making it simple to calculate without using of regression. Unlike usual…

In this paper, based on the classfication of multiparticle states and the original definition of semiseparability, we give out the redefinition of semiseparability and inseparability of multiparticle states. By virtue of the redefinition,…

Quantum Physics · Physics 2009-11-10 Chang-shui Yu , He-shan Song

Entanglement speeds up evolution of a pure bipartite spin state, in line with the time energy uncertainty. However if the state is mixed this is not necessarily the case. We provide a counter example and point to other factors affecting…

Quantum Physics · Physics 2009-11-13 Judy Kupferman , Benni Reznik

We consider a class of entangled states of a quantum system (S) and a second system (A) where pure states of the former are correlated with mixed states of the latter, and work out the entanglement measure with reference to the nearest…

Quantum Physics · Physics 2008-07-04 Avijit Lahiri , Gautam Ghosh , Sankhasubhra Nag

We propose an explicit formula for an entanglement measure of pure multipartite quantum states, then study a general pure tripartite state in detail, and at end we give some simple but illustrative examples on four-qubits and m-qubits…

Quantum Physics · Physics 2016-08-16 Hoshang Heydari , Gunnar Björk

An entanglement measure for a bipartite quantum system is a state functional that vanishes on separable states and that does not increase under separable (local) operations. It is well-known that for pure states, essentially all…

Quantum Physics · Physics 2025-08-22 Stefan Hollands , Ko Sanders

We present a new set of inseparabilty inequalities to detect entanglement in $N$-spin states. These are based on negative partial transposition and involve collective spin-spin correlations of any two partitions of the entire system. They…

Quantum Physics · Physics 2016-08-08 Asoka Biswas

We present the entanglement properties of the spin-orbital coupling systems with multiple degrees of freedom. After constructing the maximally entangled spin-orbital basis of bipartite, we find that the quantum entanglement length in the…

Strongly Correlated Electrons · Physics 2007-05-23 Dong-Meng Chen , Wei-Hua Wang , Liang-Jian Zou

Entanglement properties of a basic set of eight entangled three particle pure states possessing certain permutation symmetries are studied. They fall into four sets of two entangled states, differing in their patterns of robustness to…

Quantum Physics · Physics 2009-11-07 A. K. Rajagopal , R. W. Rendell

It is shown that the geometric measure of entanglement of a pure multipartite state satisfies a polynomial equation, generalising the characteristic equation of the matrix of coefficients of a bipartite state. The equation is solved for a…

Quantum Physics · Physics 2010-07-06 Joseph J. Hilling , Anthony Sudbery

We investigate the behavior of genuine multiparticle entanglement, as quantified by the generalized geometric measure, in gapless-to-gapped quantum transitions of one- and two-dimensional quantum spin models. The investigations are…

Quantum Physics · Physics 2014-09-09 Anindya Biswas , R. Prabhu , Aditi Sen De , Ujjwal Sen

We investigate the competition between pair entanglement of two spin qubits in double quantum dots attached to leads with various topologies and the separate entanglement of each spin with nearby electrodes. Universal behavior of…

Quantum Physics · Physics 2015-06-26 A. Ramsak , J. Mravlje , R. Zitko , J. Bonca

he multiqubit entangled states are coherently controlled in the quantum spin systems composed of $N+1$ interacting antiferromagnetic molecular rings. The tunable intermolecular couplings arise from the local exchange interactions between…

Quantum Physics · Physics 2009-03-17 Xiang Hao , Tao Pan , Taocheng Zang , Shiqun Zhu

Anticoherent spin states have isotropic low-order spin moments and are relevant to direction-independent metrology and quantum reference-frame alignment. In contrast to pure states, for mixed states such isotropy may originate either from…

Quantum Physics · Physics 2026-05-29 Jérôme Denis , Tara Lacaille , John Martin , Eduardo Serrano-Ensástiga

Multipartite entanglement is the premier resource for quantum technologies. Yet, its exact quantification in the laboratory is notoriously challenging, typically requiring the full knowledge of high dimensional quantum states. Here, we…

Quantum Physics · Physics 2026-05-05 Francois Payn , Davide Girolami

Based on the residual entanglement [9] (Phys. Rev. A \textbf{71}, 044301 (2005)), we present the global entanglement for a multipartite quantum state. The measure is shown to be also obtained by the bipartite partitions of the multipartite…

Quantum Physics · Physics 2009-11-13 Chang-shui Yu , He-shan Song

We give an elementary introduction to the notion of quantum entanglement between distinguishable parties and review a recent proposal about solid state quantum computation with spin-qubits in quantum dots. The indistinguishable character of…

Condensed Matter · Physics 2007-05-23 John Schliemann , Daniel Loss

We explore some basic entanglement features of multiqubit systems that are relevant for the development of algorithms for searching highly entangled states. In particular, we compare the behaviours of multiqubit entanglement measures based…

Quantum Physics · Physics 2009-01-26 A. Borras , M. Casas , A. R. Plastino , A. Plastino