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Related papers: Measure of Entaglement

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We consider entanglement in a system of fixed number of identical particles. Since any operation should be symmetrized over all the identical particles and there is the precondition that the spatial wave functions overlap, the meaning of…

Quantum Physics · Physics 2009-11-07 Yu Shi

Entanglement does not correspond to any observable and its evaluation always corresponds to an estimation procedure where the amount of entanglement is inferred from the measurements of one or more proper observables. Here we address…

Quantum Physics · Physics 2009-11-13 Marco G. Genoni , Paolo Giorda , Matteo G. A. Paris

We propose a measure of entanglement that can be computed for any pure state of an $M$-qubit system. The entanglement measure has the form of a distance that we derive from an adapted application of the Fubini-Study metric. This measure is…

In a good physical theory dimensionless quantities such as the ratio m_p / m_e of the mass of the proton to the mass of the electron do not depend on the system of units being used. This paper demonstrates that one widely used method for…

Quantum Physics · Physics 2009-11-06 M. A. Nielsen

For systems consisting of distinguishable particles, there exists an agreed upon notion of entanglement which is fundamentally based on the possibility of addressing individually each one of the constituent parties. Instead, the…

Quantum Physics · Physics 2020-09-24 F. Benatti , R. Floreanini , F. Franchini , U. Marzolino

The act of measuring optical emissions from two remote qubits can entangle them. By demanding that a photon from each qubit reaches the detectors, one can ensure than no photon was lost. But the failure rate then rises quadratically with…

Quantum Physics · Physics 2009-06-09 Earl T. Campbell , Simon C. Benjamin

An entangled quantum state of two or more particles or objects exhibits some of the most peculiar features of quantum mechanics. Entangled systems cannot be described independently of each other even though they may have an arbitrarily…

Mesoscale and Nanoscale Physics · Physics 2018-04-27 C. F. Ockeloen-Korppi , E. Damskagg , J. -M. Pirkkalainen , A. A. Clerk , F. Massel , M. J. Woolley , M. A. Sillanpaa

Distinguishability and predictability are part of complementarity relations which apply to two different kinds of interference experiments, with and without a path-detector, respectively. In [Opt. Comm. 179, 337 (2000)], Englert and Bergou…

Quantum Physics · Physics 2021-12-07 Marcos L. W. Basso , Jonas Maziero

The measurement of high-dimensional entangled states of orbital angular momentum prepared by spontaneous parametric down-conversion can be considered in two separate stages: a generation stage and a detection stage. Given a certain number…

Quantum Physics · Physics 2015-06-03 F. M. Miatto , D. Giovannini , J. Romero , S. Franke-Arnold , S. M. Barnett , M. J. Padgett

The quantification of quantum entanglement is a central issue in quantum information theory. Recently, Gao \emph{et al}. ( \href{http://dx.doi.org/10.1103/PhysRevLett.112.180501}{Phys. Rev. Lett. \textbf{112}, 180501 (2014)}) pointed out…

Quantum Physics · Physics 2021-05-11 Xianfei Qi , Ting Gao , Fengli Yan

We introduce geometric measures of entanglement for indistinguishable particles, which apply to mixed states, multipartite systems, and arbitrary dimensions. They are based on generalized (i.e., not necessarily finite) norms on the set of…

Quantum Physics · Physics 2015-07-17 Florian Sokoli , Burkhard Kümmerer

Entanglement is the key feature of many-body quantum systems, and the development of new tools to probe it in the laboratory is an outstanding challenge. Measuring the entropy of different partitions of a quantum system provides a way to…

Multipartite entanglement is an essential resource for quantum communication, quantum computing, quantum sensing, and quantum networks. The utility of a quantum state, $|\psi\rangle$, for these applications is often directly related to the…

Quantum Physics · Physics 2022-01-05 Jacob L. Beckey , N. Gigena , Patrick J. Coles , M. Cerezo

Maximally entangled mixed states are those states that, for a given mixedness, achieve the greatest possible entanglement. For two-qubit systems and for various combinations of entanglement and mixedness measures, the form of the…

Entanglement depth characterizes the minimal number of particles in a system that are mutually entangled. For symmetric states, we show that there is a dichotomy for entanglement depth: an $N$-particle symmetric state is either fully…

Quantum Physics · Physics 2016-11-02 Ji-Yao Chen , Zhengfeng Ji , Nengkun Yu , Bei Zeng

We study partial coherence and its connections with entanglement. First, we provide a sufficient and necessary condition for bipartite pure state transformation under partial incoherent operations: A bipartite pure state can be transformed…

Quantum Physics · Physics 2023-07-17 Sunho Kim , Chunhe Xiong , Shunlong Luo , Asutosh Kumar , Junde Wu

The notion of a macroscopic quantum state must be pinned down in order to assess how well experiments probe the large-scale limits of quantum mechanics. However, the issue of quantifying so-called quantum macroscopicity is fraught with…

Quantum Physics · Physics 2025-03-12 Benjamin Yadin , Matteo Fadel

We suggest scattering experiments which implement the concept of ``protective measurements'' allowing the measurement of the complete wave function even when only one quantum system (rather than an ensemble) is available. Such scattering…

Quantum Physics · Physics 2009-10-30 S. Nussinov

To quantify the entanglement is one of the most important topics in quantum entanglement theory. In [arXiv: 2006.12408], the authors proposed a method to build a measure from the orginal domain to a larger one. Here we apply that method to…

Quantum Physics · Physics 2021-04-21 Xian Shi , Lin Chen

Measurement in quantum mechanics is generally described as an irreversible process that perturbs the wavefunction describing a quantum system. In this work we establish a formal connection between the measurement description within the…

Quantum Physics · Physics 2016-05-17 Fabio L. Traversa , Guillermo Albareda