English
Related papers

Related papers: Internal Boundary between Entanglement and Separab…

200 papers

For a random quantum state on $H=C^d \otimes C^d$ obtained by partial tracing a random pure state on $H \otimes C^s$, we consider the whether it is typically separable or typically entangled. For this problem, we show the existence of a…

Quantum Physics · Physics 2015-05-12 Guillaume Aubrun , Stanislaw J. Szarek , Deping Ye

In early days of quantum theory it was believed that the results of measurements performed on two distant physical systems should be uncorrelated thus their quantum state should be separable it means described by a simple tensor product of…

Quantum Physics · Physics 2012-10-26 Marian Kupczynski

Separability problem, to decide whether a given state is entangled or not, is a fundamental problem in quantum information theory. We propose a powerful and computationally simple separability criterion, which allows us to detect the…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yong-Sheng Zhang , Shun Zhang , Guang-Can Guo

The geometric measure of entanglement of a pure quantum state is defined to be its distance to the space of product (seperable) states. Given an $n$-partite system composed of subsystems of dimensions $d_1,\ldots, d_n$, an upper bound for…

Quantum Physics · Physics 2018-05-09 Liqun Qi , Guofeng Zhang , Guyan Ni

Quantum entanglement is a key physical resource in quantum information processing that allows for performing basic quantum tasks such as teleportation and quantum key distribution, which are impossible in the classical world. Ever since the…

Quantum Physics · Physics 2020-07-29 Xin Wang , Mark M. Wilde

Our investigation aims to study the specific role played by entanglement in the quantum computation process, by elaborating an entangled spin model developed within the 'hidden measurement approach' to quantum mechanics. We show that an…

Quantum Physics · Physics 2007-05-23 Diederik Aerts , Ellie D'Hondt , Bart D'Hooghe

As one of the most profound features of quantum mechanics, entanglement is a vital resource for quantum information processing. Inspired by the recent work on PT-moments and separablity [Phys. Rev. Lett. {\bf 127}, 060504 (2021)], we…

Quantum Physics · Physics 2024-02-21 Xiaofen Huang , Naihuan Jing

We discuss the concept of how entanglement changes with respect to different factorizations of the total algebra which describes the quantum states. Depending on the considered factorization a quantum state appears either entangled or…

Quantum Physics · Physics 2011-11-15 Walter Thirring , Reinhold A. Bertlmann , Philipp Köhler , Heide Narnhofer

Quantum entanglement of pure states of a bipartite system is defined as the amount of local or marginal ({\em i.e.}referring to the subsystems) entropy. For mixed states this identification vanishes, since the global loss of information…

Quantum Physics · Physics 2007-05-23 Gerardo Adesso , Alessio Serafini , Fabrizio Illuminati

We argue from the point of view of statistical inference that the quantum relative entropy is a good measure for distinguishing between two quantum states (or two classes of quantum states) described by density matrices. We extend this…

Quantum Physics · Physics 2009-10-30 V. Vedral , M. B. Plenio , K. Jacobs , P. L. Knight

We develop a strong and computationally simple entanglement criterion. The criterion is based on an elementary positive map Phi which operates on state spaces with even dimension N >= 4. It is shown that Phi detects many entangled states…

Quantum Physics · Physics 2007-05-23 Heinz-Peter Breuer

The initialization of a quantum system into a certain state is a crucial aspect of quantum information science. While a variety of measurement strategies have been developed to characterize how well the system is initialized, for a given…

The structural study of entanglement in multipartite systems is hindered by the lack of necessary and sufficient operational criteria able to discriminate among the various entanglement properties of a given mixed state. Here, we pursue a…

Quantum Physics · Physics 2014-05-20 Ruben Quesada , Anna Sanpera

In quantum information theory, the reliable and effective detection of entanglement is of paramount importance. However, given an unknown state, assessing its entanglement is a challenging task. To attack this problem, we investigate the…

Quantum Physics · Physics 2015-12-09 Jochen Szangolies , Hermann Kampermann , Dagmar Bruß

The degree of entanglement is determined for an arbitrary state of a broad class of PT-symmetric bipartite composite systems. Subsequently we quantify the rate with which entangled states are generated and show that this rate can be…

High Energy Physics - Theory · Physics 2013-05-23 Christian Zielinski , Qing-hai Wang

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings [A. Shimony, Ann. NY.…

Quantum Physics · Physics 2007-05-23 Tzu-Chieh Wei , Paul M. Goldbart

We propose an algorithm which proves a given bipartite quantum state to be separable in a finite number of steps. Our approach is based on the search for a decomposition via a countable subset of product states, which is dense within all…

Quantum Physics · Physics 2009-11-10 Florian Hulpke , Dagmar Bruss

This short note describes a method to tackle the (bipartite) quantum separability problem. The method can be used for solving the separability problem in an experimental setting as well as in the purely mathematical setting. The idea is to…

Quantum Physics · Physics 2007-05-23 L. M. Ioannou , B. C. Travaglione

Bound entangled states are states that are entangled but from which no entanglement can be distilled if all parties are allowed only local operations and classical communication. However, in creating these states one needs nonzero…

Quantum Physics · Physics 2009-11-10 Tzu-Chieh Wei , Joseph B. Altepeter , Paul M. Goldbart , William J. Munro

Detecting entanglement in multipartite quantum states is an inherently probabilistic process, typically with a few measured samples. The level of confidence in entanglement detection quantifies the scheme's validity via the probability that…