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Related papers: Geometric Phase in Entangled Systems: A Single-Neu…

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We propose and analyze a protocol for observing a violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality using two spatially separated Bose-Einstein condensates (BECs). To prepare the Bell-correlated state, spin-changing…

We combine the concept of Bell measurements, in which two systems are projected into a maximally entangled state, with the concept of continuous measurements, which concerns the evolution of a continuously monitored quantum system. For such…

Quantum Physics · Physics 2013-10-24 Sebastian G. Hofer , Denis V. Vasilyev , Markus Aspelmeyer , Klemens Hammerer

Any pure three-qubit state is uniquely characterized by one phase and four positive parameters. The geometric measure of entanglement as a function of state parameters can have different expressions. Each of expressions has its own…

Quantum Physics · Physics 2009-09-08 Sayatnova Tamaryan , Hungsoo Kim , Mu-Seong Kim , Kap Soo Jang , DaeKil Park

All previous tests of local realism have studied correlations between single-particle measurements. In the present experiment, we have performed a Bell experiment on three particles in which one of the measurements corresponds to a…

Quantum Physics · Physics 2009-11-11 Philip Walther , Kevin J. Resch , Caslav Brukner , Anton Zeilinger

The geometric phase effect arises from the dependence on the nuclear coordinates in the electronic Hamiltonian, leading to sign changes of the electronic wave functions upon traversal of certain paths in nuclear configuration space. The…

Chemical Physics · Physics 2025-08-15 Eirik F. Kjønstad , Henrik Koch

Violation of Bell inequalities is an essential requirement for many quantum information and communication protocols. In high-dimensional systems, Bell inequality tests face the challenge of implementing genuinely multi-outcome measurements,…

The geometric measure of entanglement is the distance or angle between an entangled target state and the nearest unentangled state. Often one considers the geometric measure of entanglement for highly symmetric entangled states because it…

Quantum Physics · Physics 2015-12-14 M. E. Carrington , G. Kunstatter , J. Perron , S. Plosker

It is conjectured that the spatial structure of quantum field states is influenced by a new kind of directional indeterminacy of quantum geometry set by the Planck length, $l_P$, that does not occur in a classical background geometry.…

General Relativity and Quantum Cosmology · Physics 2014-12-05 Craig J. Hogan

The Clauser-Horne-Shimony-Holt (CHSH) inequality (and its permutations), are necessary and sufficient criteria for Bell nonlocality in the simplest Bell-nonlocality scenario: 2 parties, 2 measurements per party and 2 outcomes per…

Quantum Physics · Physics 2015-06-30 Eric G. Cavalcanti , Christopher J. Foster , Maria Fuwa , Howard M. Wiseman

Geometric entanglement(GE), as a measure of multipartite entanglement, has been investigated as a universal tool to detect phase transitions in quantum many-body lattice models. We outline a systematic method to compute GE for…

Strongly Correlated Electrons · Physics 2019-09-06 Qian-Qian Shi , Hong-Lei Wang , Sheng-Hao Li , Sam Young Cho , Murray T. Batchelor , Huan-Qiang Zhou

A Greenberger Horne Zeilinger (GHZ) entangled state with a phase is crucial for realizing desired multipartite quantum states for practical applications. Here, we report violations of the general Bell inequality (GBI) introduced in [1]…

Quantum Physics · Physics 2023-03-16 Jiho Park , Junghee Ryu , Heonoh Kim , Han Seb Moon

The degree to which a pure quantum state is entangled can be characterized by the distance or angle to the nearest unentangled state. This geometric measure of entanglement, already present in a number of settings [A. Shimony, Ann. NY.…

Quantum Physics · Physics 2007-05-23 Tzu-Chieh Wei , Paul M. Goldbart

The entanglement swapping protocol is analyzed in a relativistic setting, where shortly after the entanglement swapping is performed, a Bell violation measurement is performed. From an observer in the laboratory frame, a Bell violation is…

Bipartite temporal Bell inequalities are similar to the usual Bell inequalities except that, instead of changing the direction of the polariser at each measurement, one changes the time at which the measurement is being performed. By doing…

Quantum Physics · Physics 2020-11-18 Kenta Ando , Vincent Vennin

Off-diagonal geometric phases acquired in the evolution of a spin-1/2 system have been investigated by means of a polarized neutron interferometer. Final counts with and without polarization analysis enable us to observe simultaneously the…

Quantum Physics · Physics 2009-11-07 Y. Hasegawa , R. Loidl , G. Badurek , M. Baron , N. Manini , F. Pistolesi , H. Rauch

We present a phase space formalism to evaluate Bell inequality violations in continuous variable systems. By doing so we can generalize previous analyses (which have dealt only with pure states) to arbitrary mixed states. We leverage these…

Quantum Physics · Physics 2025-01-09 Gurpahul Singh , Kelly Wurtz , Eduardo Martín-Martínez

We quantify the geometric measure of entanglement in terms of mean values of observables of entangled system. For pure states we find the relation of geometric measure of entanglement with the mean value of spin one-half for the system…

Quantum Physics · Physics 2017-10-11 A. M. Frydryszak , M. I. Samar , V. M. Tkachuk

We introduce a geometric framework for studying Bell nonlocality in Hilbert space, where, for a given quantum state, nonlocality is quantified by the distance between the state and the set of local states. This approach applies to any Bell…

When elliptically polarized maximally entangled states are considered, i.e., states having a non random phase factor between the two bipartite polarization components, the standard settings used for optimal violation of Bell inequalities…

We study the entanglement evolution of the set of Bell diagonal states for a two-qubit system coupled to two independent vacuum noise sources. This set can be represented geometrically as the set of points inside a tetrahedron in a…

Quantum Physics · Physics 2015-01-09 Ramsés Sánchez , Esteban Isasi , Douglas Mundarain