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Related papers: Converting Nonclassicality into Entanglement

200 papers

We extend the concept of classicality in quantum optics to spin states. We call a state ``classical'' if its density matrix can be decomposed as a weighted sum of angular momentum coherent states with positive weights. Classical spin states…

Quantum Physics · Physics 2010-06-23 Olivier Giraud , Petr Braun , Daniel Braun

Quantum entanglement manifests as a distinctive correlation between particles that transcends classical boundaries when their quantum states cannot be described independently. On the other hand, as quantum systems interact with their…

Quantum Physics · Physics 2025-08-21 Samuel Marquez Gonzalez

Description of nonclassicality of states has hitherto been through violation of Bell inequality and non-separability, with the latter being a stronger constraint. In this paper, we show that this can be further sharpened, by introducing the…

Quantum Physics · Physics 2015-06-18 H. M. Bharath , V. Ravishankar

In this paper it is shown that the quantum state of a multiverse made up of classically disconnected regions of the space-time, whose dynamical evolution is dominated by a homogeneous and isotropic fluid, is given by a squeezed state. These…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Salvador Robles-Perez , Pedro F. Gonzalez-Diaz

Nonclassical states are essential for optics-based quantum information processing, but their fragility limits their utility for practical scenarios in which loss and noise inevitably degrade, if not destroy, nonclassicality. Exploiting…

Quantum Physics · Physics 2015-03-25 Zheshen Zhang , Sara Mouradian , Franco N. C. Wong , Jeffrey H. Shapiro

We generalize the classical probability frame by adopting a wider family of random variables that includes nondeterministic ones. The frame that emerges is known to host a ''classical'' extension of quantum mechanics. We discuss the notion…

Quantum Physics · Physics 2007-05-23 E. G. Beltrametti , S. Bugajski

We demonstrate in theory and experiment the strict equivalence between nonclassical polarization and the entanglement of indistinguishable photons, thereby unifying these two phenomena that appear dissimilar at first sight. This allows us…

The nonclassicality of a macroscopic single-mode optical superposition state is potentially convertible into entanglement, when the state is mixed with the vacuum on a beam splitter. Considering light beams with polarization degree of…

Quantum Physics · Physics 2024-06-27 Minghui Li , Wei Wang , Zikang Tang , Hou Ian

In this paper, we study the bipartite entanglement of spin coherent states in the case of pure and mixed states. By a proper choice of the subsystem spins, the entanglement for large class of quantum systems is investigated. We generalize…

Quantum Physics · Physics 2015-06-12 K. Berrada , A. Mohammadzade , S. Abdel-Khalek , H. Eleuch , S. Salimi

Entanglement, a defining property of quantum mechanics in which two physical subsystems cannot be seen as independent entities, challenges our everyday experience and classical intuition. However, only such strong quantum correlations…

Quantum Physics · Physics 2025-11-13 Enno Giese

It is possible to construct a classical, macroscopic system which has a mathematical structure that is exactly the same as that of a quantum mechanical system and which can be put into a state which is identical to quantum mechanical…

Quantum Physics · Physics 2014-06-30 D. W. Snoke

Coherent superposition and entanglement are two fundamental aspects of non-classicality. Here we provide a quantitative connection between the two on the level of operations by showing that the dynamical coherence of an operation upper…

Quantum Physics · Physics 2020-10-01 Thomas Theurer , Saipriya Satyajit , Martin B. Plenio

Quantum theory features several phenomena which can be considered as resources for information processing tasks. Some of these effects, such as entanglement, arise in a nonlocal scenario, where a quantum state is distributed between…

Quantum Physics · Physics 2024-07-22 Martin Plávala , Otfried Gühne

Identical particles and entanglement are both fundamental components of quantum mechanics. However, when identical particles are condensed in a single spatial mode, the standard notions of entanglement, based on clearly identifiable…

Quantum Physics · Physics 2014-04-23 N. Killoran , M. Cramer , M. B. Plenio

We consider pure quantum states of $N\gg 1$ spins or qubits and study the average entanglement that can be \emph{localized} between two separated spins by performing local measurements on the other individual spins. We show that all…

Quantum Physics · Physics 2007-05-23 F. Verstraete , M. Popp , J. I. Cirac

In this work, we consider two spins initially prepared in a product of coherent states and study their entanglement dynamics due to a general interacting Hamiltonian. We adopt an approach that allowed the derivation of a semiclassical…

Quantum Physics · Physics 2021-11-03 Matheus V. Scherer , Alexandre D. Ribeiro

This paper presents an alternative approach to quantum entanglement, one that effectively resolves the logical inconsistencies without leading to logical contradictions. By addressing some of the inconsistencies within quantum mechanics,…

Quantum Physics · Physics 2024-05-15 Pouria Abbasalinejad , Hamid Tebyanian

Quantum entanglement obscures the notion of local operations; there exist quantum states for which all local actions on one subsystem can be equivalently realized by actions on another. We characterize the states for which this fundamental…

Quantum Physics · Physics 2020-02-14 Ilan Tzitrin , Aaron Z. Goldberg , Jesse C. Cresswell

We introduce a generalization of entanglement based on the idea that entanglement is relative to a distinguished subspace of observables rather than a distinguished subsystem decomposition. A pure quantum state is entangled relative to such…

Quantum Physics · Physics 2009-11-10 Howard Barnum , Emanuel Knill , Gerardo Ortiz , Rolando Somma , Lorenza Viola

Entanglement is widely considered the cornerstone of quantum information and an essential resource for relevant quantum effects, such as quantum teleportation, quantum cryptography, or the speed-up of quantum computing, as in Shor's…

Quantum Physics · Physics 2017-01-13 M. Sanz , I. L. Egusquiza , R. Di Candia , H. Saberi , L. Lamata , E. Solano