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Related papers: Witnessing entanglement beyond decoherence

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Detecting entanglement in multipartite quantum states is an inherently probabilistic process, typically with a few measured samples. The level of confidence in entanglement detection quantifies the scheme's validity via the probability that…

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 investigate quantum features and non-classical nature of two-spin-$1/2$ NMR systems at thermal equilibrium under external magnetic fields. More specifically, using suitable quantifiers, we analyze quantum coherence, mixedness, and…

Quantum Physics · Physics 2025-12-02 Fatemeh Khashami

We study the quantumness of correlations for ensembles of bi- and multi-partite systems and relate it to the task of quantum data hiding. Quantumness is here intended in the sense of minimum average disturbance under local measurements. We…

Quantum Physics · Physics 2014-12-02 Marco Piani , Varun Narasimhachar , John Calsamiglia

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

Interpretations of quantum measurement theory have been plagued by two questions, one concerning the role of observer consciousness and the other the entanglement phenomenon arising from the superposition of quantum states. We emphasize…

Quantum Physics · Physics 2007-05-23 L. E. H. Trainor , Charles J. Lumsden

We propose a new measure of quantum entanglement. Our measure is defined in terms of conditional information transmission for a Quantum Bayesian Net. We show that our measure is identically equal to the Entanglement of Formation in the case…

Quantum Physics · Physics 2007-05-23 Robert R. Tucci

Entanglement detection typically relies on linear inequalities for mean values of certain observables (entanglement witnesses), where violation indicates entanglement. We provide a general method to improve any of these inequalities for…

Quantum Physics · Physics 2007-05-23 Otfried Gühne , Norbert Lütkenhaus

Sensors that harness exclusively quantum phenomena (such as entanglement) can achieve superior performance compared to those employing only classical principles. Recently, a technique based on postselected, weakly-performed measurements has…

Quantum Physics · Physics 2013-01-18 George C. Knee , G. Andrew D. Briggs , Simon C. Benjamin , Erik M. Gauger

Typicality arguments replace the postulated mixed state ensembles of statistical mechanics with pure states sampled uniformly at random, explaining why most microstates of large systems exhibit thermal behavior. This paradigm has been…

Quantum Physics · Physics 2025-05-01 Pedro S. Correia , Gabriel Dias Carvalho , Thiago R. de Oliveira

We recently showed that multipartite correlations between outcomes of random observables detect quantum entanglement in all pure and some mixed states. In this followup article we further develop this approach, derive a maximal amount of…

Quantum Physics · Physics 2016-10-11 Minh Cong Tran , Borivoje Dakic , Wieslaw Laskowski , Tomasz Paterek

In quantum physics, measurement results are random but their statistics can be predicted assuming some knowledge about the system in the past. Additional knowledge from a future measurement deeply changes the statistics in the present and…

Quantum entanglement is one of the core features of quantum theory. While it is typically revealed by measurements along carefully chosen directions, here we review different methods based on so-called random or randomized measurements.…

Quantum Physics · Physics 2020-11-24 Lukas Knips

Quantum entanglement manifests itself in non-local correlations between the constituents of a system. In its simplest realization, a measurement on one subsystem is affected by a prior measurement on its partner, irrespective of their…

Quantum Physics · Physics 2026-01-09 Gilles Parez , William Witczak-Krempa

We provide a summary of both seminal and recent results on typical entanglement. By typical values of entanglement, we refer here to values of entanglement quantifiers that (given a reasonable measure on the manifold of states) appear with…

Quantum Physics · Physics 2014-09-05 Oscar C. O. Dahlsten , Cosmo Lupo , Stefano Mancini , Alessio Serafini

We consider a class of entangled states of a quantum system (S) and a second system (A) where pure states of the former are correlated with mixed states of the latter, and work out the entanglement measure with reference to the nearest…

Quantum Physics · Physics 2008-07-04 Avijit Lahiri , Gautam Ghosh , Sankhasubhra Nag

We review studies of entanglement entropy in systems with quenched randomness, concentrating on universal behavior at strongly random quantum critical points. The disorder-averaged entanglement entropy provides insight into the quantum…

Disordered Systems and Neural Networks · Physics 2015-05-13 Gil Refael , Joel E. Moore

We discuss stochastic resonance-like effects in the context of coupled quantum spin systems. We focus here on an information-theoretic approach and analyze the steady state quantum correlations (entanglement) as well as the global…

Quantum Physics · Physics 2009-05-14 Ángel Rivas , Neil P. Oxtoby , Susana F. Huelga

Detecting entanglement in many-body quantum systems is crucial but challenging, typically requiring multiple measurements. Here, we establish the class of states where measuring connected correlations in just $\textit{one}$ basis is…

Quantum Physics · Physics 2024-04-05 Roopayan Ghosh , Sougato Bose

A non-ergodic quantum state of a many body system is in general random as well as multi-parametric, former due to a lack of exact information due to complexity and latter reflecting its varied behavior in different parts of the Hilbert…

Quantum Physics · Physics 2023-06-21 Devanshu Shekhar , Pragya Shukla
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