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Related papers: Entanglement and Impropriety

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We show how a straightforward Bayesian updating procedure allows one to detect and quantify entanglement from any finite set of measurement results. The measurements do not have to be tomographically complete, and may consist of POVMs…

Quantum Physics · Physics 2009-08-03 Pavel Lougovski , S. J. van Enk

These two accompanying papers treat two mode entanglement for systems of identical massive bosons and the relationship to spin squeezing and other quantum correlation effects. Entanglement is a key quantum feature of composite systems where…

Quantum Physics · Physics 2016-01-07 Bryan Dalton , John Goold , Barry Garraway , Margaret Reid

We explore the effect of two-dimensional position-space non-commutativity on the bipartite entanglement of continuous variable systems. We first extend the standard symplectic framework for studying entanglement of Gaussian states of…

Quantum Physics · Physics 2013-05-29 S. Adhikari , B. Chakraborty , A. S. Majumdar , S. Vaidya

Quantum entanglement lies at the heart of quantum mechanics in both fundamental and practical aspects. The entanglement of quantum states has been studied widely, however, the entanglement of operators has not been studied much in spite of…

We report on the effects of quantum interference induced by transmission of an arbitrary number of optical quantum states through a multiple scattering medium. We identify the role of quantum interference on the photon correlations and the…

Quantum Physics · Physics 2010-08-31 J. R. Ott , N. A. Mortensen , P. Lodahl

Although a precise description of microscopic physical problems requires a full quantum mechanical treatment, physical quantities are generally discussed in terms of classical variables. One exception is quantum entanglement which…

Quantum Physics · Physics 2015-05-30 A. Ramsak

We investigate the entanglement patterns of photon-added and -subtracted four-mode squeezed vacuum states. Entanglements in different scenarios are analyzed by varying the number of photons added or subtracted in certain modes, which are…

Quantum Physics · Physics 2016-05-18 Tamoghna Das , R. Prabhu , Aditi Sen De , Ujjwal Sen

A measurement scheme of atomic qubits pinned at given positions is studied by analyzing the interference pattern obtained when they emit photons spontaneously. In the case of two qubits, a well-known relation is revisited, in which the…

Quantum Physics · Physics 2015-05-18 Jun Suzuki , Christian Miniatura , Kae Nemoto

Common notions of entanglement are based on well-separated subsystems. However, obtaining such independent degrees of freedom is not always possible because of physical constraints. In this work, we explore the notion of entanglement in the…

Quantum Physics · Physics 2025-04-08 Franziska Barkhausen , Laura Ares Santos , Stefan Schumacher , Jan Sperling

We investigate how the entanglement characteristics of a non-Gaussian entangled state are increased or decreased by a local photon subtraction operation. The non-Gaussian entangled state is generated by injecting a single-mode non-Gaussian…

Quantum Physics · Physics 2015-06-16 Su-Yong Lee , Se-Wan Ji , Chang-Woo Lee

We suggest an experimentally realizable scheme to test entanglement of a mixed Gaussian continuous variable state. We find that the entanglement condition is simplified for the family of Gaussian states which are relevant to experimental…

Quantum Physics · Physics 2007-05-23 M. S. Kim , Jinhyoung Lee

The phenomenon of quantum entanglement is explained in a way which is fully consistent with Einstein's Special Theory of Relativity. A subtle flaw is identified in the logic supporting the view that Bell's Inequality precludes all local…

Quantum Physics · Physics 2007-05-23 Jeremy L. Fellows

The role of the timing and order of quantum measurements is not just a fundamental question of quantum mechanics, but also a puzzling one. Any part of a quantum system that has finished evolving, can be measured immediately or saved for…

Quantum Physics · Physics 2014-02-04 E. Megidish , A. Halevy , T. Shacham , T. Dvir , L. Dovrat , H. S. Eisenberg

We present several entanglement conditions in order to detect bound entangled states in continuous variable systems. Specifically, Werner and Wolf [Phys. Rev. Lett. 86, 3658 (2001)] and Horodecki and Lewenstein [Phys. Rev. Lett. 85, 2657…

Quantum Physics · Physics 2015-05-19 Cheng-Jie Zhang , Hyunchul Nha , Yong-Sheng Zhang , Guang-Can Guo

Entanglement is a physical resource of a quantum system just like mass, charge or energy. Moreover it is an essential tool for many purposes of nowadays quantum information processing, e.g. quantum teleportation, quantum cryptography or…

Disordered Systems and Neural Networks · Physics 2008-02-15 Imre Varga , Jose Antonio Mendez-Bermudez

An uncertainty relation is introduced for a symmetric arrangement of three mutually unbiased bases in continuous variable phase space, and then used to derive a bipartite entanglement criterion based on the variance of global operators…

Quantum Physics · Physics 2017-02-17 E. C. Paul , D. S. Tasca , Lukasz Rudnicki , S. P. Walborn

Multipartite entanglement and nonclassicality of four-mode Gaussian states generated in two simultaneous nonlinear processes involving parametric down-conversion and frequency up-conversion are analyzed assuming the vacuum as the initial…

Quantum Physics · Physics 2016-09-26 Ievgen I. Arkhipov , Jan Peřina , Ondřej Haderka , Alessia Allevi , Maria Bondani

We predict the occurrence of single-photon-induced entanglement and quantum superposition in a hybrid quantum model, introducing an optomechanical coupling into the Rabi model. Originally, it comes from the photon-dependent quantum property…

Quantum Physics · Physics 2018-03-29 Xin-You Lü , Gui-Lei Zhu , Li-Li Zheng , Ying Wu

The pairwise entanglement of an arbitrary atomic pair randomly extracted from a laser-driven dense multiqubit sample in the presence of quantum dissipation due to spontaneous emission is considered. The dipole-dipole interaction between the…

Quantum Physics · Physics 2015-05-14 M. Macovei , J. Evers , C. H. Keitel

Quantum nonlocality is arguably among the most counter-intuitive phenomena predicted by quantum theory. In recent years, the development of an abstract theory of nonlocality has brought a much deeper understanding of the subject. In…