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Related papers: On the covariance matrix for Gaussian states

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Non-Gaussianity is a key resource for achieving quantum advantages in bosonic platforms. Here, we investigate the symplectic rank: a novel non-Gaussianity monotone that satisfies remarkable operational and resource-theoretic properties.…

We present a novel approach to the separability problem for Gaussian quantum states of bosonic continuous variable systems. We derive a simplified necessary and sufficient separability criterion for arbitrary Gaussian states of $m$ vs $n$…

Quantum Physics · Physics 2018-02-22 Ludovico Lami , Alessio Serafini , Gerardo Adesso

The study of Gaussian states has arisen to a privileged position in continuous variable quantum information in recent years. This is due to vehemently pursued experimental realisations and a magnificently elegant mathematical framework. In…

Quantum Physics · Physics 2014-03-17 Gerardo Adesso , Sammy Ragy , Antony R. Lee

This paper combines probabilistic and algebraic techniques for computing quantum expectations of operator exponentials (and their products) of quadratic forms of quantum variables in Gaussian states. Such quadratic-exponential functionals…

Quantum Physics · Physics 2018-09-19 Igor G. Vladimirov , Ian R. Petersen , Matthew R. James

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

Gaussian quantum states of bosonic systems are an important class of states. In particular, they play a key role in quantum optics as all processes generated by Hamiltonians up to second order in the field operators (i.e. linear optics and…

Quantum Physics · Physics 2022-03-31 Jonatan Bohr Brask

A Gaussian fluctuation formula is proved for linear statistics of complex random matrices in the case that the statistic is rotationally invariant. For a general linear statistic without this symmetry, Coulomb gas theory is used to predict…

Statistical Mechanics · Physics 2007-05-23 P. J. Forrester

We review the theory of continuous-variable entanglement with special emphasis on foundational aspects, conceptual structures, and mathematical methods. Much attention is devoted to the discussion of separability criteria and entanglement…

Quantum Physics · Physics 2009-07-02 Gerardo Adesso , Fabrizio Illuminati

This is an introductory note concerning the distribution vectors in a unitary representation of a Lie group. We discuss the definition of matrix coefficients associated with a pair of distributions and how one can compute them. Most of the…

Functional Analysis · Mathematics 2022-01-03 Hongyu He

Minimum-uncertainty squeezed states, related to a broad class of observables, are analyzed. Methods for characterizing such states are developed, which are based on numerical solutions of ordinary differential equations. As typical examples…

Quantum Physics · Physics 2007-12-24 E. Shchukin , W. Vogel , Th. Kiesel

We construct the general permutation invariant Gaussian 2-matrix model for matrices of arbitrary size $D$. The parameters of the model are given in terms of variables defined using the representation theory of the symmetric group $S_D$. A…

High Energy Physics - Theory · Physics 2022-03-30 George Barnes , Adrian Padellaro , Sanjaye Ramgoolam

Quantum entanglement reflects itself through non-local correlations among the subsystems of a quantum system. This thesis focuses on constructing a complete set of local invariants characterizing symmetric two qubit systems and analyzing…

Quantum Physics · Physics 2009-07-14 M. S. Uma

The Gaussian unitary random matrix ensembles satisfying some additional symmetry conditions are considered. The effect of these conditions on the limiting normalized counting measures and correlation functions is studied.

Mathematical Physics · Physics 2008-04-24 Vladimir Vasilchuk

We explore conditions on the covariance matrices of a consistent chain of mean zero finite mode Gaussian states in order that the chain may be exchangeable or stationary. For an exchangeable chain our conditions are necessary and…

Quantum Physics · Physics 2015-10-16 K. R. Parthasarathy , Ritabrata Sengupta

We discuss and investigate the geometrical structure of general multipartite states. In particular, we show that a geometrical measure of entanglement for general multipartite states can be constructed by the complex projective varieties…

Quantum Physics · Physics 2007-08-23 Hoshang Heydari

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 provide a new and simple characterization of the multivariate generalized Laplace distribution. In particular, this result implies that the product of a Gaussian matrix with independent and identically distributed columns by an…

Probability · Mathematics 2017-04-06 Pierre-Alexandre Mattei

We introduce new families of pure quantum states that are constructed on top of the well-known Gilmore-Perelomov group-theoretic coherent states. We do this by constructing unitaries as the exponential of operators quadratic in Cartan…

Quantum Physics · Physics 2021-05-12 Tommaso Guaita , Lucas Hackl , Tao Shi , Eugene Demler , J. Ignacio Cirac

We derive a hierarchy of separability criteria for multi-mode continuous variable systems. They permit to study in a unified way the k-partite entanglement of broad classes of Gaussian and non- Gaussian states. With specific examples we…

Quantum Physics · Physics 2014-11-25 Antonio A. Valido , Federico Levi , Florian Mintert

We discuss probabilistic models of random covariance structures defined by distributions over sparse eigenmatrices. The decomposition of orthogonal matrices in terms of Givens rotations defines a natural, interpretable framework for…

Methodology · Statistics 2022-06-07 Andrew J. Cron , Mike West