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

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The quantification of quantum coherence has attracted a growing attention, and based on various physical contexts, several coherence measures have been put forward. An interesting question is whether these coherence measures give the same…

Quantum Physics · Physics 2016-09-20 C. L. Liu , Xiao-Dong Yu , G. F. Xu , D. M. Tong

Quantum steering can be detected via the violation of steering inequalities, which provide sufficient conditions for the steerability of quantum states. Here we discuss the converse problem, namely ensuring that a state is unsteerable, and…

Quantum Physics · Physics 2016-03-21 Joseph Bowles , Flavien Hirsch , Marco Túlio Quintino , Nicolas Brunner

One-way quantum deficit and quantum discord are two important measures of quantum correlations. We revisit the relationship between them in two-qubit systems. We investigate the conditions that both one-way quantum deficit and quantum…

Quantum Physics · Physics 2016-01-12 Biao-Liang Ye , Shao-Ming Fei

It has been proven that the quantum discord is a more general tool to capture non-classical correlation than quantum entanglement, because there is a non-zero quantum discord in several mixed states that could not be measured by quantum…

Quantum Physics · Physics 2015-03-20 N. Doustimotlagh

Like entanglement, quantum discord quantifies the quantum correlations. Unlike entanglement, whose detection is extremely difficult, the quantum discord of an arbitrary bipartite state allows itself to be detected perfectly by a single…

Quantum Physics · Physics 2011-02-24 Sixia Yu , Chengjie Zhang , Qing Chen , C. H. Oh

Experimental determination of entanglement is important not only to characterize the state and use it in quantum information, but also in understanding complicated phenomena such as phase transitions. In this paper we show that in many…

Quantum Physics · Physics 2016-01-20 Gaurav Chaudhary , V. Ravishankar

We study the level surfaces of quantum discord for a class of two-qubit states with parallel nonzero Bloch vectors. The dynamic behavior of quantum discord under decoherence is investigated. It is shown that a class of X states has sudden…

Quantum Physics · Physics 2011-04-12 Bo Li , Zhi-Xi Wang , Shao-Ming Fei

The relation between genuine multipartite entanglement in the pure state of a collection of N qubits and the nonclassical correlations in its two-qubit subsystems is studied. Quantum discord is used as the quantifier of nonclassical…

Quantum Physics · Physics 2022-08-31 Chandan Mahto , Vijay Pathak , Ardra K. S. , Anil Shaji

We consider a general version of the phenomenon of more nonlocality with less entanglement, within the framework of the unambiguous (i.e., conclusive) quantum state discrimination problem under local quantum operations and classical…

Quantum Physics · Physics 2022-03-25 Saronath Halder , Ujjwal Sen

In this paper, we present schemes for a type of one-parameter bipartite quantum states to probe the quantum entanglement, the quantum discord, the classical correlation and the quantum state based on the cavity QED. It is shown that our…

Quantum Physics · Physics 2015-06-16 Zhen-ni Li , Jia-sen Jin , Chang-shui Yu

Quantum entanglement and quantum non-locality are known to exhibit monogamy, that is, they obey strong constraints on how they can be distributed among multipartite systems. Quantum correlations that comprise and go beyond entanglement are…

Quantum Physics · Physics 2012-08-03 Alexander Streltsov , Gerardo Adesso , Marco Piani , Dagmar Bruss

So far, super quantum discord has been calculated explicitly only for Bell-diagonal states and expressions for more general quantum states are not known. In this paper, we derive explicit expressions for super quantum discord for a larger…

Quantum Physics · Physics 2014-09-16 H. Eftekhari , E. Faizi

The quantumness of a generic state is the resource of many applications in quantum information theory and it is interesting to survey the measures which are able to detect its trace in the properties of the state. In this work we study the…

Quantum Physics · Physics 2016-04-26 Javad Behdani , Seyed Javad Akhtarshenas , Mohsen Sarbishaei

Quantum Discord (QD) is a measure of the total quantum non-local correlations of a quantum system. The formalism of quantum discord has been applied to various two-qubit mixed states and it has been reported that there is a non-zero quantum…

Quantum Physics · Physics 2022-10-04 M. S. Ramkarthik , Devvrat Tiwari , Pranay Barkataki

Quantum discord, a measure of genuinely quantum correlations, is generalized to continuous variable systems. For all two-mode Gaussian states, we calculate analytically the quantum discord and a related measure of classical correlations,…

Quantum Physics · Physics 2015-03-13 Gerardo Adesso , Animesh Datta

We classify multipartite entanglement in a unified manner, focusing on a duality between the set of separable states and that of entangled states. Hyperdeterminants, derived from the duality, are natural generalizations of entanglement…

Quantum Physics · Physics 2007-05-23 Akimasa Miyake , Miki Wadati

We evaluate analytically the quantum discord for a large family of multiqubit states. It is interesting to note that the quantum discord of three-qubits and five-qubits is the same, as is the quantum discord of two-qubits and six-qubits. We…

Quantum Physics · Physics 2021-08-04 Bo Li , Chen-Lu Zhu , Xiao-Bin Liang , Biao-Liang Ye , Shao-Ming Fei

Local unitary operations allow for a unifying approach to the quantification of quantum correlations among the constituents of a bipartite quantum system. For pure states, the distance between a given state and its image under…

Quantum Physics · Physics 2015-10-23 M. Cianciaruso , S. M. Giampaolo , W. Roga , G. Zonzo , M. Blasone , F. Illuminati

A set of Bell inequalities classifying the quantum entanglement of four-qubit states is presented. These inequalities involve only two measurement settings per observer and can characterize fully separable, bi-separable and tri-separable…

Quantum Physics · Physics 2013-07-26 Hui Zhao , Xing-Hua Zhang , Shao-Ming Fei , Zhi-Xi Wang

Quantum correlations represent a fundamental tool for studies ranging from basic science to quantum technologies. Different non-classical correlations have been identified and studied, as entanglement and discord. In view of future…

Quantum Physics · Physics 2016-12-15 E. Moreva , M. Gramegna , M. A. Yurischev , M. Genovese