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Related papers: On two-qubit states ordering with quantum discords

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The state disturbance induced by locally measuring a quantum system yields a signature of nonclassical correlations beyond entanglement. Here we present a detailed study of such correlations for two-qubit mixed states. To overcome the…

Quantum Physics · Physics 2011-08-22 Davide Girolami , Mauro Paternostro , Gerardo Adesso

We show that bipartite bound entangled states make possible violations of correlation inequalities in the prepare-and-measure scenario. These inequalities are satisfied by all classical models as well as by all quantum models that do not…

Quantum Physics · Physics 2025-03-28 Carles Roch I Carceller , Armin Tavakoli

Quantum correlations in multiple quantum (MQ) NMR experiments are investigated in two-spin systems (dimers). In the initial moment of time one spin is in a pure quantum polarized state and the other spin is in the thermodynamic equilibrium…

Quantum Physics · Physics 2017-01-16 S. A. Gerasev , E. I. Kuznetsova

There is a direct correspondence between two-particle, entangled quantum states, for example, Bell states, and the relative values of the component one-particle states. This leads to a new rationale for quantum computing which makes use of…

Quantum Physics · Physics 2007-05-23 R. G. Beil

The presence of quantum correlations in a quantum state is related to the state response to local unitary perturbations. Such response is quantified by the distance between the unperturbed and perturbed states, minimized with respect to…

Quantum Physics · Physics 2014-08-25 W. Roga , S. M. Giampaolo , F. Illuminati

Quantum discord is an optimal resource for the quantification of classical and non-classical correlations as compared to other related measures. Geometric measure of quantum discord is another measure of quantum correlations. Recently, the…

Quantum Physics · Physics 2013-08-06 M. Ramzan

The classification of the multipartite entanglement is an important problem in quantum information theory. We propose a class of two qubit mixed states $\sigma_{AB}=…

Quantum Physics · Physics 2014-08-08 Jyoti Faujdar , Anoopa Joshi , Satyabrata Adhikari

Discordant states appear in a large number of quantum phenomena and seem to be a good indicator of divergence from classicality. While there is evidence that they are essential for a quantum algorithm to have an advantage over a classical…

Quantum Physics · Physics 2013-10-04 Aharon Brodutch

We investigate bipartite entanglement in random quantum $XY$ models at equilibrium. Depending on the intrinsic time scales associated with equilibration of the random parameters and measurements associated with observation of the system, we…

Quantum Physics · Physics 2020-01-03 Anindita Bera , Debasis Sadhukhan , Debraj Rakshit , Aditi Sen De , Ujjwal Sen

We present a numerical framework for the certification and systematic analysis of the relationship between Bell nonlocality and quantum discord. By determining the minimum discord required for a bipartite state to manifest a specific Bell…

Quantum Physics · Physics 2026-05-06 Robert Okuła , Adrian Misiak , Piotr Mironowicz

Quantum entanglement is widely recognized as one of the key resources for the advantages of quantum information processing, including universal quantum computation, reduction of communication complexity or secret key distribution. However,…

Superlocality and superunsteerability provide operational characterization of quantum correlations in certain local and unsteerable states respectively. Such quantum correlated states have a nonzero quantum discord. A two-way nonzero…

Quantum Physics · Physics 2023-10-19 Chellasamy Jebarathinam , Debarshi Das , R. Srikanth

We study a behavior of two-qubit states subject to tomographic measurement. We propose a novel approach to definition of asymmetry in quantum bipartite state based on its tomographic Shannon entropies. We consider two types of measurement…

Quantum Physics · Physics 2015-03-20 Evgeny Kiktenko , Aleksey Fedorov

The study of quantum correlations in High-dimensional bipartite systems is crucial for the development of quantum computing. We propose relative entropy as a distance measure of correlations may be measured by means of the distance from the…

Quantum Physics · Physics 2016-04-12 M. Mahdian , M. B. Arjmandi

The entangled quantum states play a key role in quantum information. The association of the quantum state vector with each individual physical system in an attributive way is a source of many false paradoxes and inconsistencies. The…

Quantum Physics · Physics 2007-10-15 M. Kupczynski

A maximally entangled state is a quantum state which has maximum von Neumann entropy for each bipartition. Through proposing a new method to classify quantum states by using concurrences of pure states of a region, one can apply Bell's…

Quantum Physics · Physics 2018-08-01 Su-Kuan Chu , Chen-Te Ma , Rong-Xin Miao , Chih-Hung Wu

We investigate the lazy states, entangled states and discordant states for 2-qubit systems. We show that many lazy states are discordant, many lazy states are entangled, and many mixed entangled states are not lazy. With these…

Quantum Physics · Physics 2014-01-20 Jianwei Xu

We investigate and compare three distinguished geometric measures of bipartite quantum correlations that have been recently introduced in the literature: the geometric discord, the measurement-induced geometric discord, and the discord of…

Quantum Physics · Physics 2016-05-26 Wojciech Roga , Dominique Spehner , Fabrizio Illuminati

Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of…

Quantum Physics · Physics 2015-11-04 Davide Girolami

We examine time ordering effects in strongly, suddenly perturbed two-state quantum systems (kicked qubits) by comparing results with time ordering to results without time ordering. Simple analytic expressions are given for state occupation…

Quantum Physics · Physics 2009-08-14 L. Kaplan , Kh. Kh. Shakov , A. Chalastaras , M. Maggio , A. L. Burin , J. H. McGuire