English
Related papers

Related papers: Entanglement and squeezing in continuous-variable …

200 papers

We investigate entanglement properties of a recently introduced class of macroscopic quantum superpositions in two-mode mixed states. One of the tools we use in order to infer the entanglement in this non-Gaussian class of states is the…

Quantum Physics · Physics 2009-11-11 M. Paternostro , H. Jeong , M. S. Kim

Multipartite entanglement is a natural generalization of bipartite entanglement, but is relatively poorly understood. In this paper, we develop tools to calculate a class of multipartite entanglement measures - known as multi-invariants -…

Quantum Physics · Physics 2026-01-26 Sriram Akella , Abhijit Gadde , Jay Pandey

We consider the problem of detecting the dimensionality of entanglement with the use of correlations between measurements in randomized directions. First, exploiting the recently derived covariance matrix criterion for the entanglement…

Quantum Physics · Physics 2023-07-20 Shuheng Liu , Qiongyi He , Marcus Huber , Otfried Gühne , Giuseppe Vitagliano

We show that for a fixed amount of entanglement, two-mode squeezed states are those that maximize Einstein-Podolsky-Rosen-like correlations. We use this fact to determine the entanglement of formation for all symmetric Gaussian states…

Quantum Physics · Physics 2013-01-14 G. Giedke , M. M. Wolf , O. Krueger , R. F. Werner , J. I. Cirac

We investigate entanglement properties at quantum phase transitions of an integrable extended Hubbard model in the momentum space representation. Two elementary subsystems are recognized: the single mode of an electron, and the pair of…

Quantum Physics · Physics 2008-10-31 Alberto Anfossi , Paolo Giorda , Arianna Montorsi

A general and computable criterion for k-(in)separability in continuous multipartite quantum systems is presented. The criterion can be experimentally implemented with a finite and comparatively low number of local observables. We discuss…

Quantum Physics · Physics 2012-02-07 Andreas Gabriel , Marcus Huber , Sasa Radic , Beatrix C. Hiesmayr

We investigate the entanglement and non-locality between specific spectral components of continuous variable two-mode squeezed mixed states, identifying their limits. These spectral components are selected from output modes using filters…

Quantum Physics · Physics 2025-04-23 Souvik Agasti

The efficient witnessing and certification of entanglement is necessitated by its ubiquitous use in various aspects of quantum technologies. In the case of continuous-variable bipartite systems, the Shchukin--Vogel hierarchy gives necessary…

Quantum Physics · Physics 2025-09-09 Elena Callus , Martin Gärttner , Tobias Haas

Quantum correlations are at the core of the power of quantum information and are necessary to reach a quantum computational advantage. In the context of continuous-variable quantum systems, another necessary ressource for quantum advantages…

Quantum Physics · Physics 2024-07-26 Carlos E. Lopetegui , Mathieu Isoard , Nicolas Treps , Mattia Walschaers

Currently available separability criteria for continuous-variable states are generally based on the covariance matrix of quadrature operators. The well-known separability criterion of Duan et al. [Phys. Rev. Lett. 84, 2722 (2000)] and Simon…

Quantum Physics · Physics 2016-03-24 Anaelle Hertz , Evgueni Karpov , Aikaterini Mandilara , Nicolas J. Cerf

We investigate localization of entanglement of multimode Gaussian states into a pair of modes by local Gaussian measurements on the remaining modes and classical communication. We find that for pure states and for mixed symmetric states…

Quantum Physics · Physics 2009-11-13 Jaromir Fiurasek , Ladislav Mista

Quantum entanglement is an essential resource for quantum science and technology. However, entanglement detection and quantification, via typical entanglement measures such as linear entanglement entropy or negativity, can be a very…

Quantum Physics · Physics 2025-06-17 Diego Fallas Padilla , Mingjian Zhu , Han Pu

In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we give a description of the dynamics of entanglement for a system consisting of two uncoupled modes interacting with a thermal…

Quantum Physics · Physics 2011-02-18 Aurelian Isar

Entanglement is one of the most fascinating features arising from quantum-mechanics and of great importance for quantum information science. Of particular interest are so-called hybrid-entangled states which have the intriguing property…

We propose three criteria for identifying continuous variable entanglement between two many-particle systems with no restrictions on the quantum state of the local oscillators used in the measurements. Mistakenly asserting a coherent state…

Quantum Physics · Physics 2009-11-13 A. J. Ferris , M. K. Olsen , E. G. Cavalcanti , M. J. Davis

Entanglement is known to serve as an order parameter for true topological order in two-dimensional systems. We show how entanglement of disconnected partitions defines topological invariants for one-dimensional topological superconductors.…

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 2016-06-01 Bryan Dalton , John Goold , Barry Garraway , Margaret Reid

We give an introduction to Gaussian states and operations. A discussion of the entanglement properties of bipartite Gaussian states in terms of its covariance matrix follows. It is explained how entanglement can be witnessed using feasible…

Quantum Physics · Physics 2007-05-23 Janet Anders

In this paper, we investigate the quantum entanglement induced by phase-space noncommutativity. Both the position-position and momentum-momentum noncommutativity are incorporated to study the entanglement properties of coordinate and…

Quantum Physics · Physics 2024-01-09 Shilpa Nandi , Muklesur Rahaman , Pinaki Patra

Identical particles and entanglement are both fundamental components of quantum mechanics. However, when identical particles are condensed in a single spatial mode, the standard notions of entanglement, based on clearly identifiable…

Quantum Physics · Physics 2014-04-23 N. Killoran , M. Cramer , M. B. Plenio