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Related papers: Subsystem Purity as an Enforcer of Entanglement

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In a system where two identical two-level atoms interact with their common one-mode cavity field, it is shown that entanglement can become abruptly frozen in time, remaining at a constant value for a period of time until it begins to thaw…

Quantum Physics · Physics 2025-11-10 Luchang Niu , Joseph H. Eberly

Individual members of an ensemble of identical systems coupled to a common probe can become entangled with one another, even when they do not interact directly. We investigate how this type of multipartite entanglement is generated in the…

Quantum Physics · Physics 2009-11-10 T. E. Tessier , I. H. Deutsch , A. Delgado , I. Fuentes-Guridi

We investigate the generation of entanglement between two non interacting qubits coupled to a common reservoir. An experimental setup was conceived to encode one qubit on the polarization of an optical beam and another qubit on its…

We study the time evolution of $N_q$ two-level atoms (or qubits) interacting with a single mode of the quantised radiation field. In the case of two qubits, we show that for a set of initial conditions the reduced density matrix of the…

Quantum Physics · Physics 2015-05-13 C. E. A. Jarvis , D. A. Rodrigues , B. L. Györffy , T. P. Spiller , A. J. Short , J. F. Annett

We study the entanglement dynamics of two atoms coupled to their own Jaynes-Cummings cavities in single-excitation space. Here we use the concurrence to measure the atomic entanglement. And the partial Bell states as initial states are…

Quantum Physics · Physics 2021-02-03 Ya Yang , Yan Liu , Jing Lu , Lan Zhou

Simple examples are constructed that show the entanglement of two qubits being both increased and decreased by interactions on just one of them. One of the two qubits interacts with a third qubit, a control, that is never entangled or…

Quantum Physics · Physics 2009-11-13 Thomas F. Jordan , Anil Shaji , E. C. G. Sudarshan

We prove an upper bound on the maximal rate at which a Hamiltonian interaction can generate entanglement in a bipartite system. The scaling of this bound as a function of the subsystem dimension on which the Hamiltonian acts nontrivially is…

Quantum Physics · Physics 2013-11-06 Karel Van Acoleyen , Michaël Mariën , Frank Verstraete

The Jaynes-Cummings model is the simplest fully quantum model that describes the interaction between light and matter. We extend a previous analysis by Phoenix and Knight (S. J. D. Phoenix, P. L. Knight, Annals of Physics 186, 381). of the…

Quantum Physics · Physics 2009-11-11 E. Boukobza , D. J. Tannor

Due to the weakness of gravitational coupling, all quantum experiments up to date in which gravity plays a role utilized the field of the Earth. Since this field undergoes practically undetectable back-action from quantum particles, it…

Quantum Physics · Physics 2024-05-16 Ankit Kumar

A thermal field, which frequently appears in problems of decoherence, provides us with minimal information about the field. We study the interaction of the thermal field and a quantum system composed of two qubits and find that such a…

Quantum Physics · Physics 2016-09-08 M. S. Kim , J. Lee , D. Ahn , P. L. Knight

This research introduces the concept of the purity number, which represents the number of separable s-particle sub-states within an n-particle state ($s<n$ ). It establishes that, for any , achieving the maximum purity number is both a…

Quantum Physics · Physics 2024-08-20 Reza Hamzehofi

Quantum entanglement and its paradoxical properties hold the key to an information processing revolution. Much attention has focused recently on the challenging problem of characterizing entanglement. Entanglement for a two qubit system is…

Quantum Physics · Physics 2009-11-07 Vivien M Kendon , Kae Nemoto , William J Munro

The concurrence, a quantitative measure of the entanglement between a pair of particles, is determined for the case where the pair is extracted from a symmetric state of N two-level systems. Examples are given for both pure and mixed states…

Quantum Physics · Physics 2009-11-07 Xiaoguang Wang , Klaus Molmer

We propose an all-optical setup, which couples different degrees of freedom of a single photon, to investigate entanglement generation by a common environment. The two qubits are represented by the photon polarization and Hermite-Gauss…

We present a significantly improved scheme of entanglement detection inspired by local uncertainty relations for a system consisting of two qubits. Developing the underlying idea of local uncertainty relations, namely correlations, we…

Quantum Physics · Physics 2016-08-16 Christian Kothe , Gunnar Björk

A system, comprised of a qubit pair coupled to a common cavity, is studied with the aim of establishing qubit entanglement. This study is the sequel of the paper Phys. Rev. A 111, 043705 (2025), where similar model was investigated for an…

Quantum Physics · Physics 2026-03-24 Amit Dey

This note quantifies the continuity properties of entanglement: how much does entanglement vary if we change the entangled quantum state just a little? This question is studied for the pure state entanglement of a bipartite system and for…

Quantum Physics · Physics 2009-10-31 M. A. Nielsen

It is well known that for pure states the relative entropy of entanglement is equal to the reduced entropy, and the closest separable state is explicitly known as well. The same holds for Renyi relative entropy per recent results. We ask…

Quantum Physics · Physics 2021-02-10 Anna Vershynina

We investigate system-environment correlations based on the exact dynamics of a qubit and its environment in the framework of pure decoherence (phase damping). We focus on the relation of decoherence and the build-up of system-reservoir…

Quantum Physics · Physics 2013-05-29 A. Pernice , W. T. Strunz

The entanglement quantified by negativity of pure bipartite superposed states is studied. We show that if the entanglement is quantified by the concurrence two pure states of high fidelity to one another still have nearly the same…

Quantum Physics · Physics 2007-09-06 Yong-Cheng Ou , Heng Fan