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Related papers: A characterization of global entanglement

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The following comment is based on an article by M. Jafarpour and L. Assadi [Eur. Phys. J. D 70, 62 (2016), doi:10.1140/epjd/e2016-60555-5] which with an exploitation of Scott measure (or generalized Meyer-Wallach measure) the entanglement…

Quantum Physics · Physics 2017-09-27 Saeed Haddadi

We study entanglement in dimerized Heisenberg systems. In particular, we give exact results of ground-state pairwise entanglement for the four-qubit model by identifying a Z_2 symmetry. Although the entanglements cannot identify the…

Quantum Physics · Physics 2015-06-26 Zhe Sun , XiaoGuang Wang , AnZi Hu , You-Quan Li

In this work, we introduce a unified method to characterize and measure multipartite entanglement using the framework of thermodynamics. A family of the new entanglement measures is proposed: \textit{ergotropic-gap concentratable…

Quantum Physics · Physics 2026-02-02 Chen-Ming Bai , Yu Luo

Multi-qubit graph states generated by the action of controlled phase shift operators on a separable quantum state of a system, in which all the qubits are in arbitrary identical states, are examined. The geometric measure of entanglement of…

Quantum Physics · Physics 2022-03-11 Kh. P. Gnatenko , N. A. Susulovska

The geometric measure of entanglement is investigated for permutation symmetric pure states of multipartite qubit systems, in particular the question of maximum entanglement. This is done with the help of the Majorana representation, which…

Quantum Physics · Physics 2010-11-02 Martin Aulbach , Damian Markham , Mio Murao

In a recent paper, Rungta et. al. [Phys. Rev. A, 64, 042315, 2001] introduced a measure of mixed-state entanglement called the I-concurrence for arbitrary pairs of qudits. We find an exact formula for an entanglement measure closely related…

Quantum Physics · Physics 2009-11-07 Tobias J. Osborne

Entanglement, and quantum correlation, are precious resources for quantum technologies implementation based on quantum information science, such as, for instance, quantum communication, quantum computing, and quantum interferometry.…

Quantum Physics · Physics 2023-05-22 Arthur Vesperini , Ghofrane Bel-Hadj-Aissa , Roberto Franzosi

We present a method to construct entanglement measures for pure states of multipartite qubit systems. The key element of our approach is an antilinear operator that we call {\em comb} in reference to the {\em hairy-ball theorem}. For qubits…

Quantum Physics · Physics 2007-05-23 Andreas Osterloh , Jens Siewert

We show how entanglement may be quantified in spin and cold atom many-body systems using standard experimental techniques only. The scheme requires no assumptions on the state in the laboratory and a lower bound to the entanglement can be…

Quantum Physics · Physics 2013-05-29 M. Cramer , M. B. Plenio , H. Wunderlich

We revisit the problem of detection of entanglement of an unknown two-qubit state using minimal resources. Using weak values and just two copies of an arbitrary two-qubit state, we present a protocol where a post selection measurement in…

Quantum Physics · Physics 2019-01-17 Suchetana Goswami , Sagnik Chakraborty , Sibasish Ghosh , A. S. Majumdar

Monogamy of entanglement is the fundamental property of quantum systems. By using two new entanglement measures based on dual entropy, the $S^{t}$-entropy entanglement and $T^{t}_q$-entropy entanglement measures, we present the general…

Quantum Physics · Physics 2024-07-19 Zhong-Xi Shen , Kang-Kang Yang , Zhi-Xiang Jin , Zhi-Xi Wang , Shao-Ming Fei

We propose a qubit-environment entanglement measure which is tailored for evolutions that lead to pure dephasing of the qubit, such as are abundant in solid state scenarios. The measure can be calculated directly form the density matrix…

Quantum Physics · Physics 2020-10-21 Katarzyna Roszak

In the standard geometric approach, the entanglement of a pure state is $\sin^2\theta$, where $\theta$ is the angle between the entangled state and the closest separable state of products of normalised qubit states. We consider here a…

Quantum Physics · Physics 2015-05-18 M. E. Carrington , R. Kobes , G. Kunstatter , D. Ostapchuk , G. Passante

We derive explicit bounds for the average entropy characterizing measurements of a pure quantum state of size $N$ in $L$ orthogonal bases. Lower bounds lead to novel entropic uncertainty relations, while upper bounds allow us to formulate…

We introduce a class of generalized geometric measures of entanglement. For pure quantum states of $N$ elementary subsystems, they are defined as the distances from the sets of $K$-separable states ($K=2,...,N$). The entire set of…

Quantum Physics · Physics 2009-07-02 M. Blasone , F. Dell'Anno , S. De Siena , F. Illuminati

Quantifying entanglement is an important issue in quantum information theory. Here we consider the entanglement measures through the trace norm in terms of two methods, the modified measure and the extended measure for bipartite states. We…

Quantum Physics · Physics 2023-02-09 Xian Shi , Lin Chen , Yixuan Liang

A measurement scheme of atomic qubits pinned at given positions is studied by analyzing the interference pattern obtained when they emit photons spontaneously. In the case of two qubits, a well-known relation is revisited, in which the…

Quantum Physics · Physics 2015-05-18 Jun Suzuki , Christian Miniatura , Kae Nemoto

An intrinsic relation between maximally entangled states and entanglement measures is revealed, which plays a role in establishing connections for different entanglement quantifiers. We exploit the basic idea and propose a framework to…

Quantum Physics · Physics 2008-11-21 Jianming Cai , Wei Song

We present an revised geometric measure of entanglement (RGME). The revised version is an entanglement monotone. Some useful inequalities about RGME are deduced. For exemplification, we give the formulas of RGME for the two-parameter class…

Quantum Physics · Physics 2007-05-23 Ya Cao , An Min Wang

We present a class of maximally entangled states generated by a high-dimensional generalisation of the \textsc{cnot} gate. The advantage of our approach is the simple algebraic structure of both entangling operator and resulting entangled…

Quantum Physics · Physics 2015-09-22 Anna Chiara Lai , Marco Pedicini , Silvia Rognone