English
Related papers

Related papers: Compatible quantum correlations: on extension prob…

200 papers

The question of whether given density operators for subsystems of a multipartite quantum system are compatible to one common total density operator is known as the quantum marginal problem. We briefly review the solution of a subclass of…

Quantum Physics · Physics 2014-04-07 Christian Schilling

A key problem in quantum information science is to determine optimal protocols for the interconversion of entangled states shared between remote parties. While for two parties a large number of results in this direction is available, the…

Quantum Physics · Physics 2025-05-26 Alexander Streltsov

We investigate quantum states that posses both maximum entanglement and maximum discord between the pertinent parties. Since entanglement (discord) is defined only for bipartite (two qubit) systems, we shall introduce an appropriate sum…

Quantum Physics · Physics 2013-03-27 J. Batle , M. Casas , A. Plastino

We investigate the separability properties of quantum states described by an extended Werner density matrix, where the classical component exhibits statistical dependence. By generalizing the classical part to allow correlations, we…

General Physics · Physics 2025-07-22 Toru Ohira

For a bi-partite quantum system defined in a finite dimensional Hilbert space we investigate in what sense entanglement change and interactions imply each other. For this purpose we introduce an entanglement operator, which is then shown to…

Quantum Physics · Physics 2009-11-07 J. Gemmer , G. Mahler

We propose a natural generalization of bipartite Werner and isotropic states to multipartite systems consisting of an arbitrary even number of d-dimensional subsystems (qudits). These generalized states are invariant under the action of…

Quantum Physics · Physics 2009-11-13 Dariusz Chruscinski , Andrzej Kossakowski

Steerability is a characteristic of quantum correlations lying in between entanglement and Bell nonlocality. Understanding how these steering correlations can be shared between different parties has profound applications in ensuring…

Quantum Physics · Physics 2020-11-11 Biswajit Paul , Kaushiki Mukherjee

The reduction criterion is a well known necessary condition for separable states, and states violating this condition are entangled and also 1-distillable. In this paper we introduce a new set of necessary conditions for separability of…

Quantum Physics · Physics 2009-11-11 William Hall

A scheme for multiparty quantum state sharing of an arbitrary two-particle state is presented with Einstein-Podolsky-Rosen pairs. Any one of the $N$ agents has the access to regenerate the original state with two local unitary operations if…

Quantum Physics · Physics 2007-05-23 Fu-Guo Deng , Xi-Han Li , Chun-Yan Li , Ping Zhou , Hong-Yu Zhou

A simple relation is introduced for concurrence to describe how much the entanglement of bipartite system is at least left if either (or both) subsystem undergoes an arbitrary physical process. This provides a lower bound for concurrence of…

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

Modern applications in quantum computation and quantum communication require the precise characterization of quantum states and quantum channels. In practice, this means that one has to determine the quantum capacity of a physical system in…

Quantum Physics · Physics 2016-04-04 D. Bruns , J. Sperling , S. Scheel

The problems of genuine multipartite entanglement detection and classification are challenging. We show that a multipartite quantum state is genuine multipartite entangled if the multipartite concurrence is larger than certain quantities…

Quantum Physics · Physics 2015-12-31 Ming Li , Shao-Ming Fei , Xianqing Li-Jost , Heng Fan

The decompositions of separable Werner state, and also isotropic state, are well-known tough issues in quantum information theory, in this work we investigate them in the Bloch vector representation, exploring the symmetric informationally…

Quantum Physics · Physics 2021-08-10 Ma-Cheng Yang , Jun-Li Li , Cong-Feng Qiao

We introduce a new family of separability criteria that are based on the existence of extensions of a bipartite quantum state $\rho$ to a larger number of parties satisfying certain symmetry properties. It can be easily shown that all…

Quantum Physics · Physics 2007-05-23 Andrew C. Doherty , Pablo A. Parrilo , Federico M. Spedalieri

The quantum coherence of a multipartite system is investigated when some of the parties are moving with uniform acceleration and the analysis is carried out using the single mode approximation. Due to acceleration the quantum coherence is…

A bipartite state is classical with respect to party $A$ if and only if party $A$ can perform nondisruptive local state identification (NDLID) by a projective measurement. Motivated by this we introduce a class of quantum correlation…

Quantum Physics · Physics 2016-04-19 Azam Kheirollahi , Seyed Javad Akhtarshenas , Hamidreza Mohammadi

We examine bipartite and multipartite correlations within the construct of unitary orbits. We show that the set of product states is a very small subset of set of all possible states, while all unitary orbits contain classically correlated…

Quantum Physics · Physics 2015-02-11 Kavan Modi , Mile Gu

We analyze the properties of entangled random pure states of a quantum system partitioned into two smaller subsystems of dimensions $N$ and $M$. Framing the problem in terms of random matrices with a fixed-trace constraint, we establish,…

Statistical Mechanics · Physics 2016-05-11 Pierpaolo Vivo , Mauricio P. Pato , Gleb Oshanin

We present a novel inequality on the purity of a bipartite state depending solely on the difference of the local Bloch vector lengths. For two qubits this inequality is tight for all marginal states and so extends the previously known…

Quantum Physics · Physics 2024-01-23 Simon Morelli , Christopher Eltschka , Marcus Huber , Jens Siewert

We study the separability of permutationally symmetric quantum states. We show that for bipartite symmetric systems most of the relevant entanglement criteria coincide. However, we provide a method to generate examples of bound entangled…

Quantum Physics · Physics 2009-05-12 Geza Toth , Otfried Gühne