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Related papers: A Geometric Diagram of Separable States

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We show that all density operators of 2$\times N$--dimensional quantum systems that remain invariant after partial transposition with respect to the first system are separable. Based on this criterion, we derive a sufficient separability…

Quantum Physics · Physics 2007-05-23 M. Lewenstein , J. I. Cirac , S. Karnas

In this paper we prove a separability criterion for mixed states in $\mathbb C^p\otimes\mathbb C^q$. We also show that the density matrix of a graph with only one entangled edge is entangled.

Information Theory · Computer Science 2007-07-13 Hadi Rahiminia , Massoud Amini

We present a description of entanglement in composite quantum systems in terms of symplectic geometry. We provide a symplectic characterization of sets of equally entangled states as orbits of group actions in the space of states. In…

Mathematical Physics · Physics 2016-01-19 Adam Sawicki , Alan Huckleberry , Marek Kuś

In this paper, we consider a system of homogeneous algebraic equations in complex variables and their conjugates, which arise naturally from the range criterion for separability of PPT states. We examine systematically these equations to…

Quantum Physics · Physics 2015-06-02 Young-Hoon Kiem , Seung-Hyeok Kye , Joohan Na

Motivated by the notions of $k$-extendability and complete extendability of the state of a finite level quantum system as described by Doherty et al (Phys. Rev. A, 69:022308), we introduce parallel definitions in the context of Gaussian…

Quantum Physics · Physics 2017-09-13 B. V. Rajarama Bhat , K. R. Parthasarathy , Ritabrata Sengupta

We investigate classification and detection of entanglement of multipartite quantum states in a very general setting, and obtain efficient $k$-separability criteria for mixed multipartite states in arbitrary dimensional quantum systems.…

Quantum Physics · Physics 2013-11-26 Ting Gao , Yan Hong , Yao Lu , Fengli Yan

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

A deformed differential calculus is developed based on an associative star-product. In two dimensions the Hamiltonian vector fields model the algebra of pseudo-differential operator, as used in the theory of integrable systems. Thus one…

High Energy Physics - Theory · Physics 2020-12-16 I. A. B. Strachan

The entanglement detection via local measurements can be experimentally implemented. Based on mutually unbiased measurements and general symmetric informationally complete positive-operator-valued measures, we present separability criteria…

Quantum Physics · Physics 2018-03-30 Shu-Qian Shen , Ming Li , Xianqing Li-Jost , Shao-Ming Fei

Genuine multipartite entanglement and full inseparability are two inequivalent quantum resources. Even though all genuinely multipartite entangled states are also fully inseparable, not all fully inseparable states are genuinely…

Quantum Physics · Physics 2026-05-28 Olga Leskovjanová , Klára Baksová , Jan Provazník , Ladislav Mišta, , Nicolai Friis

Using new results on the separability properties of bosonic systems, we provide a new complete criterion for separability. This criterion aims at characterizing the set of separable states from the inside by means of a sequence of…

Quantum Physics · Physics 2013-05-29 Miguel Navascues , Masaki Owari , Martin B. Plenio

Nonlocality without entanglement and its subsequent generalizations offer deep information-theoretic insights and subsequently find several useful applications. Concept of genuinely nonlocal set of product states emerges as a natural…

Quantum Physics · Physics 2023-03-31 Sumit Rout , Ananda G. Maity , Amit Mukherjee , Saronath Halder , Manik Banik

According to the geometric characterization of measurement assemblages and local hidden state (LHS) models, we propose a steering criterion which is both necessary and sufficient for two-qubit states under arbitrary measurement sets. A…

Quantum Physics · Physics 2018-11-19 Bai-Chu Yu , Zhih-Ahn Jia , Yu-Chun Wu , Guang-Can Guo

A quantum system consisting of two subsystems is separable if its density matrix can be written as $\rho=\sum_A w_A\,\rho_A'\otimes\rho_A''$, where $\rho_A'$ and $\rho_A''$ are density matrices for the two subsytems. In this Letter, it is…

Quantum Physics · Physics 2011-05-05 Asher Peres

Recent developments have revealed that symmetries need not form a group, but instead can be non-invertible. Here we use analytical arguments and numerical evidence to illuminate how spontaneous symmetry breaking of a non-invertible symmetry…

Strongly Correlated Electrons · Physics 2026-05-29 Kristian Tyn Kai Chung , Umberto Borla , Andriy H. Nevidomskyy , Sergej Moroz

In quantum many-body systems with kinetically constrained dynamics, the Hilbert space can split into exponentially many disconnected subsectors, a phenomenon known as Hilbert-space fragmentation. We study the interplay of such fragmentation…

Quantum Physics · Physics 2025-10-09 Thomas Iadecola

It is shown that a set in product of $n$ metrizable spaces is the discontinuity points set of some separately continuous function if and only if this set can be represented as the union of a sequence of $F_{\sigma}$-sets which are locally…

General Topology · Mathematics 2015-12-29 V. K. Maslyuchenko , V. V. Mykhaylyuk

We study geometrical aspects of entanglement, with the Hilbert--Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show that a ``relativistic'' formulation leads…

Quantum Physics · Physics 2013-05-29 Jon Magne Leinaas , Jan Myrheim , Eirik Ovrum

Werner and Wolf have proven in Phys. Rev. Lett. 86(16) (2001) a very elegant necessary and sufficient condition for a bosonic continuous variable bipartite Gaussian mixed quantum state to be separable. This condition is, however, difficult…

Quantum Physics · Physics 2022-10-18 Maurice de Gosson

While the exact separability probability of 8/33 for two-qubit states under the Hilbert-Schmidt measure has been reported by Huong and Khoi [\href{https://doi.org/10.1088/1751-8121/ad8493}{J.Phys.A:Math.Theor.{\bf57}, 445304(2024)}],…

Quantum Physics · Physics 2026-03-13 Lin Zhang , Xiaohan Jiang , Bing Xie