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Related papers: Spin Squeezing, Negative Correlations, and Concurr…

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We study the pairing correlations in a finite Fermi system from quantum entanglement point of view. We investigate the relation between the order parameter, which has been introduced recently to describe both finite and infinite…

Superconductivity · Physics 2009-11-07 Zafer Gedik

We discuss the canonical form for a pure state of three identical bosons in two modes, and classify its entanglement correlation into two types, the analogous GHZ and the W types as well known in a system of three distinguishable qubits. We…

Quantum Physics · Physics 2009-11-11 B. Zeng , D. L. Zhou , Z. Xu , L. You

This study investigates spin squeezed states in nuclear magnetic resonance (NMR) quadrupolar systems with spins $I=3/2$ and $I=7/2$ at room temperature, taking into account the effects of relaxation on the dynamics. The origin of spin…

We show that spin squeezing implies entanglement for quantum tripartite-state, where the subsystem of the bipartite-state is identical. We study the relation between spin squeezing parameters and entanglement through the quantum entropy of…

Quantum Physics · Physics 2015-03-13 M. S. Ateto

We investigate the presence of spin- and planar- squeezing in generalized superpositions of atomic (or spin) coherent states (ACS). Spin-squeezing has been shown to be a useful tool in determining the presence of entanglement in…

Quantum entanglement, the essential resource for quantum information processing, has rich dynamics under different environments. Probing different entanglement dynamics typically requires exquisite control of complicated system-environment…

Spin chains with open boundaries, such as the transverse field Ising model, can display coherence times for edge spins that diverge with the system size as a consequence of almost conserved operators, the so-called strong zero modes. Here,…

Statistical Mechanics · Physics 2018-10-03 Loredana M. Vasiloiu , Federico Carollo , Juan P. Garrahan

Quantum spin squeezing is an important resource for quantum information processing, but its squeezing degree is not easy to preserve in an open system with decoherence. Here, we propose a scheme to implement single-photon-triggered spin…

Quantum Physics · Physics 2021-12-01 Zhucheng Zhang , Lei Shao , Wangjun Lu , Yuguo Su , Yi-Ping Wang , Jing Liu , Xiaoguang Wang

Using parametric conversion induced by a Shapiro-type resonance, we produce and characterize a two-mode squeezed vacuum state in a sodium spin 1 Bose-Einstein condensate. Spin-changing collisions generate correlated pairs of atoms in the…

Quantum Gases · Physics 2020-07-27 An Qu , Bertrand Evrard , Jean Dalibard , Fabrice Gerbier

We study numerically the production of orbital and spin entangled states in chaotic quantum dots for non-interacting electrons. The introduction of spin-orbit coupling permit us to identify signatures of time-reversal symmetry correlations…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Diego Frustaglia , Simone Montangero , Rosario Fazio

Critical exceptional points (CEPs) are nonequilibrium critical points in open many-body systems at which multiple collective excitation modes coalesce. CEPs are known to amplify classical fluctuations, but their effect on genuinely…

Quantum Physics · Physics 2026-05-28 Yuma Nakanishi

Spin coherent states play a crucial role in defining QESM (quasi-exactly solvable models) establishing a strict correspondence between energy spectra of spin systems and low-lying quantum states for a particle moving in a potential field of…

Quantum Physics · Physics 2007-05-23 V. V. Ulyanov , O. B. Zaslavskii

Local entanglement between pairs of spins, as measured by concurrence, is investigated in a disordered spin model that displays a transition from an ergodic to a many-body localized phase in excited states. It is shown that the concurrence…

Strongly Correlated Electrons · Physics 2016-04-13 Soumya Bera , Arul Lakshminarayan

We consider two quantum dots described by the Anderson-impurity model with one electron per dot. The goal of our work is to study the decay of a maximally entangled state between the two electrons localized in the dots. We prepare the…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 C. A. Büsser , I. de Vega , F. Heidrich-Meisner

Squeezed states, a special kind of entangled states, are known as a useful resource for quantum metrology. In interferometric sensors they allow to overcome the "classical" projection noise limit stemming from the independent nature of the…

Quantum Gases · Physics 2013-02-14 Christian Gross

We introduce kicked $p$-spin models describing a family of transverse Ising-like models for an ensemble of spin-$1/2$ particles with all-to-all $p$-body interaction terms occurring periodically in time as delta-kicks. This is the natural…

Quantum Physics · Physics 2021-05-26 Manuel H. Muñoz-Arias , Pablo M. Poggi , Ivan H. Deutsch

We explore the dynamics of entanglement in classically chaotic systems by considering a multiqubit system that behaves collectively as a spin system obeying the dynamics of the quantum kicked top. In the classical limit, the kicked top…

Quantum Physics · Physics 2009-11-10 Xiaoguang Wang , Shohini Ghose , Barry C Sanders , Bambi Hu

This article studies the decoherence induced on a system of two qubits by local interactions with a spin chain with nontrivial internal dynamics (governed by an XY Hamiltonian). Special attention is payed to the transition between two…

Quantum Physics · Physics 2013-05-29 Cecilia Cormick , Juan Pablo Paz

The notion of spin squeezing involves reduction in the uncertainty of a component of the spin vector below a certain limit. This aspect has been studied earlier for pure and mixed states of definite spin. In this paper, this study has been…

Quantum Physics · Physics 2009-11-07 A. R. Usha Devi , K. S. Mallesh , Mahmoud A. A. Sbaih , K. B. Nalini , G Ramachandran

We present a method to calculate an upper bound on the generation of entanglement in any spin system using the Fannes-Audenaert inequality for the von Neumann entropy. Our method not only is useful for efficiently estimating entanglement,…

Quantum Physics · Physics 2019-04-08 Meenu Kumari , Shohini Ghose