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Related papers: Quantum discord of states arising from graphs

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Distributing quantum correlations to each node of a network is a key aspect of quantum networking. Here, we present a robust, physically motivated protocol by which global quantum correlations, as characterized by the discord, can be…

Quantum Physics · Physics 2025-01-15 Adam G. Hawkins , Hannah McAleese , Mauro Paternostro

Machine learning has achieved success in many areas because of its powerful fitting ability, so we hope it can help us to solve some significant physical quantitative problems, such as quantum correlation. In this research we will use…

Quantum Physics · Physics 2019-05-28 Yong-Lei Liu , An-Min Wang , Guo-Dong Wang , Yi Sun , Peng-Fei Zhang

Graph structures are ubiquitous throughout the natural sciences. Here we consider graph-structured quantum data and describe how to carry out its quantum machine learning via quantum neural networks. In particular, we consider training data…

Quantum Physics · Physics 2021-03-22 Kerstin Beer , Megha Khosla , Julius Köhler , Tobias J. Osborne

We consider the geometric global quantum discord (GGQD) of two-qubit systems. By analyzing the symmetry of geometric global quantum discord we give an approach for deriving analytical formulae of the extremum problem which lies at the core…

Quantum Physics · Physics 2016-02-18 Yunlong Xiao , Tao Li , Shao-Ming Fei , Naihuan Jing , Xianqing Li-Jost , Zhi-Xi Wang

We have generalised the concept of graph states to what we have called mixed graph states, which we define in terms of mixed graphs, that is graphs with both directed and undirected edges, as the density matrix stabilized by the associated…

Quantum Physics · Physics 2016-03-17 Constanza Riera , Ramij Rahaman , Matthew G. Parker

Two long standing open problems in quantum theory are to characterize the class of initial system-bath states for which quantum dynamics is equivalent to (1) a map between the initial and final system states, and (2) a completely positive…

Quantum Physics · Physics 2009-04-15 A. Shabani , D. A. Lidar

When a quantum system is divided into two local subsystems, measurements on the two subsystems can exhibit correlations beyond those possible in a classical joint probability distribution; these are partially explained by entanglement, and…

Quantum Physics · Physics 2019-06-17 Aaron Szasz

We introduce the quantum-house effect, a non-local phenomenon which apparently does not require quantum discord to be present. It suffices for the effect if neither subsystem of a bipartite system is in a pure state. This way, the…

Quantum Physics · Physics 2022-12-20 Tamás Varga

The study of classical and quantum correlations in bipartite and multipartite systems is crucial for the development of quantum information theory. Among the quantifiers adopted in tripartite systems, the genuine tripartite quantum discord…

Quantum Physics · Physics 2015-02-10 Andrea Beggi , Fabrizio Buscemi , Paolo Bordone

Correlations may arise in quantum systems through various means, of which the most remarkable one is quantum entanglement. Additionally, there are systems that exhibit non-classical correlations even in the absence of entanglement. Quantum…

Quantum Physics · Physics 2024-08-13 Gökhan Torun

A fundamental problem in quantum information is to describe efficiently multipartite quantum states. An efficient representation in terms of graphs exists for several families of quantum states (graph, cluster, stabilizer states),…

Quantum Physics · Physics 2012-07-04 Radu Ionicioiu , Tim P. Spiller

Establishing quantum correlations between two remote parties by sending an information carrier is an essential step of many protocols in quantum information processing. We obtain trade-off relations between discords and coherence within a…

Quantum Physics · Physics 2022-03-25 Zhi-Xiang Jin , Xianqing Li-Jost , Shao-Ming Fei , Cong-Feng Qiao

We highlight an information-theoretic meaning of quantum discord as the gap between the ac- cessible information and the Holevo bound in the framework of ensemble of quantum states. This complementary relationship implies that a large…

Quantum Physics · Physics 2013-03-21 Yao Yao , Jing-Zheng Huang , Xu-Bo Zou , Zhen-Qiang Yin , Wei Chen , Guang-Can Guo , Zheng-Fu Han

We propose a scheme to evaluate the amount of quantum discord and entanglement of formation for mixed states, and reveal their ordering relation via an intrinsic relationship between the two quantities distributed in different partners of…

Quantum Physics · Physics 2015-05-19 Li-Xiang Cen , Xin-Qi Li , JiuShu Shao , YiJing Yan

The "noncommutative graphs" which arise in quantum error correction are a special case of the quantum relations introduced in [N. Weaver, Quantum relations, Mem. Amer. Math. Soc. 215 (2012), v-vi, 81-140]. We use this perspective to…

Operator Algebras · Mathematics 2017-06-30 Nik Weaver

Global quantum discord (GQD), proposed by Rulli and Sarandy [Phys. Rev. A \textbf{84}, 042109 (2011)], is a generalization of quantum discord to multipartite states. In this paper, we provide an equivalent expression for GQD, and obtain the…

Quantum Physics · Physics 2012-12-13 Jianwei Xu

One of the defining differences between classical and quantum systems is how measurements affect them. Here, we compare the approaches of contextuality and quantum discord in capturing quantum correlations in special classes of two-qubit…

Quantum Physics · Physics 2022-08-11 Asma Al-Qasimi

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

We analyse the generation of quantum discord by means of the dynamical Casimir effect in superconducting waveguides modulated by superconducting quantum interferometric devices. We show that for realistic experimental parameters, the…

Quantum Physics · Physics 2015-07-17 Carlos Sabín , Ivette Fuentes , Göran Johansson

Recent measures of nonclassical correlations are motivated by different notions of classicality and operational means. Quantum discord has received a great deal of attention in studies involving quantum computation, metrology, dynamics,…

Quantum Physics · Physics 2014-05-27 Kavan Modi