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Related papers: Witnessing entanglement beyond decoherence

200 papers

We theoretically derive the probability densities of the entanglement measures of a pure non-ergodic many-body state, represented in a bipartite product basis and with its reduced density matrix described by a generalized, multi-parametric…

Quantum Physics · Physics 2024-12-11 Devanshu Shekhar , Pragya Shukla

The experimental detection of multipartite entanglement usually requires a number of appropriately chosen local quantum measurements which are aligned with respect to a previously shared common reference frame. The latter, however, can be a…

Quantum Physics · Physics 2019-04-02 Andreas Ketterer , Nikolai Wyderka , Otfried Gühne

We frame entanglement detection as a problem of random variable inference to introduce a quantitative method to measure and understand whether entanglement witnesses lead to an efficient procedure for that task. Hence we quantify how many…

Quantum Physics · Physics 2023-08-16 Paulo J. Cavalcanti , Giovanni Scala , Antonio Mandarino , Cosmo Lupo

A bipartite quantum system in a mixed state can exhibit nonclassical correlations, which can go beyond quantum entanglement. While quantum discord is the standard measure of quantifying such general quantum correlations, the nonclassicality…

Quantum Physics · Physics 2017-06-21 Amandeep Singh , Arvind , Kavita Dorai

Decoherence is the process via which quantum superpositions states are reduced to classical mixtures. Decoherence has been predicted for relativistically accelerated quantum systems, however examples to date have involved restricting the…

Quantum Physics · Physics 2019-01-16 Daiqin Su , Timothy C. Ralph

We demonstrate that generalized entanglement [Barnum {\em et al.}, Phys. Rev. A {\bf 68}, 032308 (2003)] provides a natural and reliable indicator of quantum chaotic behavior. Since generalized entanglement depends directly on a choice of…

Quantum Physics · Physics 2009-11-13 Yaakov S. Weinstein , Lorenza Viola

The detection and certification of entanglement and quantum correlations in materials is of fundamental and far-reaching importance, and has seen significant recent progress. It impacts both our understanding of the basic science of quantum…

Quantum Physics · Physics 2025-03-31 Pontus Laurell , Allen Scheie , Elbio Dagotto , D. Alan Tennant

We provide an interpretation of entanglement based on classical correlations between measurement outcomes of complementary properties: states that have correlations beyond a certain threshold are entangled. The reverse is not true, however.…

Quantum Physics · Physics 2015-05-26 Lorenzo Maccone , Dagmar Bruss , Chiara Macchiavello

The entanglement of multi-atom quantum states is considered. In order to cancel noise due to inhomogeneous light atom coupling, the concept of matched multi-atom observables is proposed. As a means to eliminate an important form of…

Quantum Physics · Physics 2009-11-10 A. Kuzmich , T. A. B. Kennedy

Coherence and entanglement are fundamental properties of quantum systems, promising to power the near future quantum computers, sensors and simulators. Yet, their experimental detection is challenging, usually requiring full reconstruction…

Quantum Physics · Physics 2017-08-01 Graeme Smith , John A. Smolin , Xiao Yuan , Qi Zhao , Davide Girolami , Xiongfeng Ma

We present a notion of generalized entanglement which goes beyond the conventional definition based on quantum subsystems. This is accomplished by directly defining entanglement as a property of quantum states relative to a distinguished…

Quantum Physics · Physics 2007-05-23 Lorenza Viola , Howard Barnum , Emanuel Knill , Gerardo Ortiz , Rolando Somma

The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Karyn Le Hur

Interaction with environment may lead to the transition of quantum system from pure state to the mixed one. In this case, the problem of definition of entanglement may arise. In particular, quantitative measure of entanglement concurrence…

Quantum Physics · Physics 2008-09-16 Levan Chotorlishvili

Assessing the quality of an ensemble of noisy entangled states is a central task in quantum information processing. Usually this is done by measuring and hence destroying multiple copies, from which state tomography or fidelity estimation…

Quantum Physics · Physics 2023-02-14 Ferran Riera-Sàbat , Jorge Miguel-Ramiro , Wolfgang Dür

How can we quantify the entanglement in a quantum state, if only the expectation value of a single observable is given? This question is of great interest for the analysis of entanglement in experiments, since in many multiparticle…

Quantum Physics · Physics 2008-05-16 O. Gühne , M. Reimpell , R. F. Werner

Although the solution, within standard quantum physics, of the problem of outcomes has been published several times, many authors continue to treat measurement as an unsolved fundamental dilemma. The solution lies in the formation of…

Quantum Physics · Physics 2022-06-14 Art Hobson

Entanglement witnesses are invaluable for efficient quantum entanglement certification without the need for expensive quantum state tomography. Yet, standard entanglement witnessing requires multiple measurements and its bounds can be…

Quantum Physics · Physics 2017-03-22 Farid Shahandeh , Martin Ringbauer , Juan C. Loredo , Timothy C. Ralph

This paper addresses the following main question: Do we have a theoretical understanding of entanglement applicable to a full variety of physical settings? It is clear that not only the assumption of distinguishability, but also the…

Quantum Physics · Physics 2007-05-23 Gerardo Ortiz , Rolando Somma , Howard Barnum , Emanuel Knill , Lorenza Viola

Quantum phenomena such as entanglement provide powerful resources for enhancing classical sensing. Here, we theoretically show that collective entanglement of spin qubits, arising from a condensation of particle-hole pairs, can strongly…

A critical requirement for diverse applications in Quantum Information Science is the capability to disseminate quantum resources over complex quantum networks. For example, the coherent distribution of entangled quantum states together…

Quantum Physics · Physics 2009-11-11 C. W. Chou , H. de Riedmatten , D. Felinto , S. V. Polyakov , S. J. van Enk , H. J. Kimble