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Related papers: Entanglement in Directed Graph States

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Graph states are versatile resources for quantum computation and quantum-enhanced measurement. Their generation illustrates a high level of control over entanglement. We report on the generation of continuous-variable graph states of atomic…

Quantum Physics · Physics 2024-07-19 Eric S. Cooper , Philipp Kunkel , Avikar Periwal , Monika Schleier-Smith

The entanglement of graph states up to eight qubits is calculated in the regime of iteration calculation. The entanglement measures could be the relative entropy of entanglement, the logarithmic robustness or the geometric measure. All 146…

Quantum Physics · Physics 2015-05-14 Xiao-yu Chen

The geometric measure of entanglement of variational quantum states is studied on the basis of its relation with the mean value of spin. We examine n-qubit quantum states prepared by a variational circuit with a layer formed by the…

Quantum Physics · Physics 2023-01-11 Kh. P. Gnatenko

This article delves into an analysis of the intrinsic entanglement and separability feature in quantum states as depicted by graph Laplacian. We show that the presence or absence of edges in the graph plays a pivotal role in defining the…

Quantum Physics · Physics 2024-01-05 Anoopa Joshi , Parvinder Singh , Atul Kumar

In the past decades, quantum entanglement has been recognized to be the basic resource in quantum information theory. A fundamental need is then the understanding its qualification and its quantification: Is the quantum state entangled, and…

Quantum Physics · Physics 2013-02-20 Szilárd Szalay

Entanglement is a fundamental resource for many applications in quantum information processing. Here, we investigate how quantum transport in simple quantum graphs, modeled as controlled two-level quantum systems, can be utilized to…

Quantum Physics · Physics 2025-10-24 Alison A. Silva , D. Bazeia , Fabiano M. Andrade

We study the entanglement distance of variational quantum states for two-qubit and multi-qubit systems. These states are constructed using variational quantum circuits with $R_Y$ rotations and entangling $CZ$ gates. For the two-qubit case,…

Quantum Physics · Physics 2026-05-29 Kh. P. Gnatenko , R. O. Hredil , V. Y. Pinchuk , M. Z. Seniak , Y. T. Shevchuk

The entanglement measure for multiqudits is proposed. This measure calculates the partial entanglement distributed by subsystems and the complete entanglement of the total system. This shows that we need to measure the subsystem…

Quantum Physics · Physics 2007-05-23 Hyuk-jae Lee , Sung Dahm Oh , Doyeol Ahn

An important problem in quantum information theory is the quantification of entanglement in multipartite mixed quantum states. In this work, a connection between the geometric measure of entanglement and a distance measure of entanglement…

Quantum Physics · Physics 2010-12-08 Alexander Streltsov , Hermann Kampermann , Dagmar Bruß

We study experimentally accessible lower bounds on entanglement measures based on entropic uncertainty relations. Experimentally quantifying entanglement is highly desired for applications of quantum simulation experiments to fundamental…

Quantum Physics · Physics 2021-05-25 Bjarne Bergh , Martin Gärttner

Graph states form a rich class of entangled states that exhibit important aspects of multi-partite entanglement. At the same time, they can be described by a number of parameters that grows only moderately with the system size. They have a…

Quantum Physics · Physics 2007-05-23 M. Hein , W. Dür , J. Eisert , R. Raussendorf , M. Van den Nest , H. -J. Briegel

Entanglement is a physical resource of a quantum system just like mass, charge or energy. Moreover it is an essential tool for many purposes of nowadays quantum information processing, e.g. quantum teleportation, quantum cryptography or…

Disordered Systems and Neural Networks · Physics 2008-02-15 Imre Varga , Jose Antonio Mendez-Bermudez

The concept of relative state is used to introduce geometric phases that originate from correlations in states of composite quantum systems. In particular, we identify an entanglement-induced geometric phase in terms of a weighted average…

Quantum Physics · Physics 2010-03-10 Erik Sjöqvist

Quantifying entanglement in quantum systems is an important yet challenging task due to its NP-hard nature. In this work, we propose an efficient algorithm for evaluating distance-based entanglement measures. Our approach builds on…

Quantum Physics · Physics 2023-08-07 Yixuan Hu , Ye-Chao Liu , Jiangwei Shang

In this paper, we study the multipartite entanglement properties of graph states up to seven qubits. Our analysis shows that the generalized concurrence measure is more efficient than geometric entanglement measure for measuring…

Quantum Physics · Physics 2023-07-20 Saeed Haddadi , Ahmad Akhound , Mohammad Ali Chaman Motlagh

Quantum entanglement between several particles is essential for applications like quantum metrology or quantum cryptography, but it is also central for foundational phenomena like quantum non-locality. This leads to the problem of…

Quantum Physics · Physics 2025-10-10 Lisa T. Weinbrenner , Otfried Gühne

We address the question of quantifying entanglement in pure graph states. Evaluation of multipartite entanglement measures is extremely hard for most pure quantum states. In this paper we demonstrate how solving one problem in graph theory,…

Quantum Physics · Physics 2013-03-04 Michal Hajdušek , Mio Murao

Our study employs a connected correlation matrix to quantify Quantum Entanglement. The matrix encompasses all necessary measures for assessing the degree of entanglement between particles. We begin with a three-qubit state and involve…

Quantum Physics · Physics 2023-12-06 Xingyu Guo , Chen-Te Ma

Entanglement for pure bipartite states is most commonly quantified in a state-by-state manner to each pure state of a bipartite system a scalar quantity, such as the von Neumann entropy of a reduced density matrix. This provides a precise…

Quantum Physics · Physics 2025-11-27 Loris Di Cairano

Computationally feasible multipartite entanglement measures are needed to advance our understanding of complex quantum systems. An entanglement measure based on the Fubini-Study metric has been recently introduced by Cocchiarella and…

Quantum Physics · Physics 2024-03-14 Matteo Gori , Matthieu Sarkis , Alexandre Tkatchenko