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Related papers: Entangled Rings

200 papers

Antiferromagnetic spin rings represent prototypical realizations of highly correlated, low-dimensional systems. Here we theoretically show how the introduction of magnetic defects by controlled chemical substitutions results in a strong…

Mesoscale and Nanoscale Physics · Physics 2015-06-11 I. Siloi , F. Troiani

We consider systems of interacting spins and study the entanglement that can be localized, on average, between two separated spins by performing local measurements on the remaining spins. This concept of Localizable Entanglement (LE) leads…

Quantum Physics · Physics 2007-05-23 M. Popp , F. Verstraete , M. A. Martin-Delgado , J. I. Cirac

How entangled is a randomly chosen bipartite stabilizer state? We show that if the number of qubits each party holds is large the state will be close to maximally entangled with probability exponentially close to one. We provide a similar…

Quantum Physics · Physics 2007-05-23 Graeme Smith , Debbie Leung

We present a detailed analysis of bipartite entanglement entropies in fractional quantum Hall (FQH) states, considering both abelian (Laughlin) and non-abelian (Moore-Read) states. We derive upper bounds for the entanglement between two…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 O. S. Zozulya , M. Haque , K. Schoutens , E. H. Rezayi

Entanglement distance is the maximal separation between two entangled electrons in a degenerate electron gas. Beyond that distance, all entanglement disappears. We relate entanglement distance to degeneracy pressure both for extreme…

Quantum Physics · Physics 2009-11-10 Christian Lunkes , Caslav Brukner , Vlatko Vedral

We discuss the estimation of the distance of a given mixed many-body quantum state to the set of fully separable states, applied to the concrete scenario of collective spin states. Concretely, we discuss lower bounds to distances from the…

Quantum Physics · Physics 2026-04-22 Julia Mathé , Ayaka Usui , Otfried Gühne , Giuseppe Vitagliano

In this paper we revisit the gravitational eikonal amplitudes of two scattering spinning particles and inspect their scrambling power in the spin spaces that is quantified through the tripartite information. We found that in the…

High Energy Physics - Theory · Physics 2023-03-07 Ling-Yan Hung , Kaixin Ji , Tianheng Wang

The entanglement of two qubits, each defined as an effective two-level, spin 1/2 system, is investigated for the case that the qubits interact via a Heisenberg XY interaction and are subject to decoherence due to population relaxation and…

Quantum Physics · Physics 2007-05-23 Jin Wang , Herman Batelaan , Jeremy Podany , Anthony F. Starace

Quantum entanglement between several particles is essential for applications like quantum metrology or quantum cryptography, but it is also central for foundational phenomena like quantum non-locality. This leads to the problem of…

Quantum Physics · Physics 2025-10-10 Lisa T. Weinbrenner , Otfried Gühne

The degree of entanglement is determined for an arbitrary state of a broad class of PT-symmetric bipartite composite systems. Subsequently we quantify the rate with which entangled states are generated and show that this rate can be…

High Energy Physics - Theory · Physics 2013-05-23 Christian Zielinski , Qing-hai Wang

Self-interactions and interaction with the environment tend to push quantum systems toward states of maximal entanglement. This is a definition of decoherence. We argue that these maximally entangled states fall into the well-defined…

Quantum Physics · Physics 2022-10-17 Roman V. Buniy , Robert P. Feger , Thomas W. Kephart

We begin by deriving bounds for the entanglement of a spin with an (adjacent and non-adjacent) interval of spins in an arbitrary pure Finitely Correlated States (FCS). The bounds we derive become exact in the case where one considers the…

Quantum Physics · Physics 2008-07-31 Spyridon Michalakis

We study the formation of an entangled state in a one-dimensional chain of three nuclear spins system which interact weakly through the Ising type of interaction and taking into account first and second neighbor interactions. We can get…

Quantum Physics · Physics 2007-05-23 Gustavo V. Lopez , Lorena Lara

Quantum no-cloning, the impossibility of perfectly cloning an arbitrary unknown quantum state, is one of the most fundamental limitations due to the laws of quantum mechanics, which underpin the physical security of quantum key…

All the states of N qubits can be classified into N-1 entanglement classes from 2-entangled to N-entangled (fully entangled) states. Each class of entangled states is characterized by an entanglement index that depends on the partition of…

Quantum Physics · Physics 2016-11-10 Sixia Yu , Zeng-Bing Chen , Jian-Wei Pan , Yong-De Zhang

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

The concept of entanglement splitting is introduced by asking whether it is possible for a party possessing half of a pure bipartite quantum state to transfer some of his entanglement with the other party to a third party. We describe the…

Quantum Physics · Physics 2009-10-31 Dagmar Bruss

It is well known that for pure states the relative entropy of entanglement is equal to the reduced entropy, and the closest separable state is explicitly known as well. The same holds for Renyi relative entropy per recent results. We ask…

Quantum Physics · Physics 2021-02-10 Anna Vershynina

We consider the use of N spin-1/2 particles for indicating a direction in space. If N>2, their optimal state is entangled. For large N, the mean square error decreases as N^{-2} (rather than N^{-1} for parallel spins).

Quantum Physics · Physics 2009-11-06 Asher Peres , Petra F. Scudo

The concept of entanglement, in which coherent quantum states become inextricably correlated, has evolved from one of the most startling and controversial outcomes of quantum mechanics to the enabling principle of emerging technologies such…