English
Related papers

Related papers: Complete criterion for convex-Gaussian state detec…

200 papers

The paper investigated a set of non-Gaussian states generated by measuring the number of particles in one of the modes of a two-mode entangled Gaussian state. It was demonstrated that all generated states depend on two types of parameters:…

Quantum Physics · Physics 2025-01-14 S. B. Korolev , E. N. Bashmakova , T. Yu. Golubeva

We prove, using symplectic methods and The Wigner formalism, a refinement of a criterion due to Werner and Wolf for the separability of bipartite Gaussian mixed states in an arbitrary number of dimensions. We use our result to show that one…

Quantum Physics · Physics 2018-09-26 Maurice A. de Gosson

The convex set of quantum states of a composite $K \times K$ system with positive partial transpose is analysed. A version of the hit and run algorithm is used to generate a sequence of random points covering this set uniformly and an…

Quantum Physics · Physics 2019-02-27 Konrad Szymański , Benoît Collins , Tomasz Szarek , Karol Życzkowski

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

Several inequivalent definitions of the geometric measure of entanglement (GM) have been introduced and studied in the past. Here we review several known and new definitions, with the qualifying criterion being that for pure states the…

Quantum Physics · Physics 2014-04-18 Lin Chen , Martin Aulbach , Michal Hajdusek

We propose a new measure of the nonclassical distance in the case of Gaussian states. Let us consider two Gaussian states one of which is fixed and the other runs through the set of Gaussian classical states. The maximum value of the…

Quantum Physics · Physics 2007-05-23 Horia Scutaru

Inspired by the definition of the non-Gaussian two-parametric continuous variable analogue of an isotropic state introduced by Mi\v{s}ta et al. [Phys. Rev. A, 65, 062315 (2002); arXiv:quant-ph/0112062], we propose to take the Gaussian part…

Quantum Physics · Physics 2021-10-04 Maria Poxleitner , Haye Hinrichsen

Deterministic discrimination of nonorthogonal states is forbidden by quantum measurement theory. However, if we do not want to succeed all the time, i.e. allow for inconclusive outcomes to occur, then unambiguous discrimination becomes…

Quantum Physics · Physics 2009-11-11 Janos Bergou , Ulrike Herzog , Mark Hillery

Approximating a quantum state by the convex mixing of some given states has strong experimental significance and provides potential applications in quantum resource theory. Here we find a closed form of the minimal distance in the sense of…

Quantum Physics · Physics 2022-02-23 Li-qiang Zhang , Nan-nan Zhou , Chang-shui Yu

We investigate the entanglement of n-mode n-partite Gaussian fermionic states (GFS). First, we identify a reasonable definition of separability for GFS and derive a standard form for mixed states, to which any state can be mapped via…

Quantum Physics · Physics 2018-04-25 Cornelia Spee , Katharina Schwaiger , Géza Giedke , Barbara Kraus

We consider the distinguishability of Gaussian states from the view point of continuous-variable quantum cryptography using post-selection. Specifically, we use the probability of error to distinguish between two pure coherent (squeezed)…

Quantum Physics · Physics 2015-05-13 Christian Weedbrook , Daniel J. Alton , Thomas Symul , Ping Koy Lam , Timothy C. Ralph

In this paper for a class of symmetric multiparty pure states we consider a conjecture related to the geometric measure of entanglement: 'for a symmetric pure state, the closest product state in terms of the fidelity can be chosen as a…

Quantum Physics · Physics 2009-12-31 Masahito Hayashi , Damian Markham , Mio Murao , Masaki Owari , Shashank Virmani

Detecting when a quantum state leaves the efficiently simulable fermionic Gaussian regime is a central task for benchmarking quantum devices and certifying fermionic magic resources. We develop practical tests and witnesses based on…

Quantum Physics · Physics 2026-05-27 Tobias Haug , Xhek Turkeshi , Piotr Sierant

The Gaussian Correlation Conjecture states that for any two symmetric, convex sets in n-dimensional space and for any centered, Gaussian measure on that space, the measure of the intersection is greater than or equal to the product of the…

Probability · Mathematics 2016-09-06 Gideon Schechtman , Thomas Schlumprecht , Joel Zinn

We provide a unified graphical calculus for all Gaussian pure states, including graph transformation rules for all local and semi-local Gaussian unitary operations, as well as local quadrature measurements. We then use this graphical…

Quantum Physics · Physics 2011-04-29 Nicolas C. Menicucci , Steven T. Flammia , Peter van Loock

The set of all separable quantum states is compact and convex. We focus on the two-qubit quanum system and study the boundary of the set. Then we give the criterion to determine whether a separable state is on the boundary. Some…

Quantum Physics · Physics 2007-05-23 Mingjun Shi , Jiangfeng Du

Capturing the correlation emerging between constituents of many-body systems accurately is one of the key challenges for the appropriate description of various systems whose properties are underpinned by quantum mechanical fundamentals.…

Quantum Physics · Physics 2023-08-17 Yannic Rath

We derive a necessary and sufficient condition for the separability of tripartite three mode Gaussian states, that is easy to check for any such state. We give a classification of the separability properties of those systems and show how to…

Quantum Physics · Physics 2009-11-07 Geza Giedke , Barbara Kraus , Maciej Lewenstein , J. Ignacio Cirac

General Probabilistic Theories provide the most general mathematical framework for the theory of probability in an operationally natural manner, and generalize classical and quantum theories. In this article, we study state-discrimination…

Quantum Physics · Physics 2010-09-15 Koji Nuida , Gen Kimura , Takayuki Miyadera

While several measures exist for entanglement of multipartite pure states, a true entanglement measure for mixed states still eludes us. A deeper study of the geometry of quantum states may be the way to address this issue, on which context…

Quantum Physics · Physics 2024-12-24 Dharmaraj Ramachandran , Radhika Vathsan