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Related papers: Wigner negativity in spin-$j$ systems

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The Wigner function's behavior of accelerated and non-accelerated Greenberger Horne Zeilinger (GHZ) state is discussed. For the non-accelerated GHZ state, the minimum/maximum peaks of the Wigner function depends on the distribution's…

Quantum Physics · Physics 2019-01-28 N. Metwally , M. Y. Abd Rabbou , M. M. A. Ahmed , A. S. F. Obada

It has recently been shown that it is possible to represent the complete quantum state of any system as a phase-space quasi-probability distribution (Wigner function) [Phys Rev Lett 117, 180401]. Such functions take the form of expectation…

Quantum Physics · Physics 2017-08-16 R. P. Rundle , P. W. Mills , Todd Tilma , J. H. Samson , M. J. Everitt

Following the information-based approach to Dirac spinors under a constant magnetic field, the phase-space representation of symmetric and anti-symmetric localized Dirac cat states is obtained. The intrinsic entanglement profile implied by…

Quantum Physics · Physics 2021-11-05 Caio Fernando e Silva , Alex E. Bernardini

We study the constructions of Dicke states of identical particles of spin-$1$, $3/2$ and $2$ in the number representation with given particle number $N$ and magnetic quantum number $M$. The complete bases and corresponding coefficients in…

Quantum Physics · Physics 2015-11-12 Wan-Fang Liu , Zheng-Da Hu

We apply the Wigner function formalism from quantum optics via two approaches, Wootters' discrete Wigner function and the generalized Wigner function, to detect quantum phase transitions in critical spin-$\tfrac{1}{2}$ systems. We develop a…

Quantum Physics · Physics 2019-09-09 Zakaria Mzaouali , Steve Campbell , Morad El Baz

Phase-space representations as given by Wigner functions are a powerful tool for representing the quantum state and characterizing its time evolution in the case of infinite-dimensional quantum systems and have been widely used in quantum…

Quantum Physics · Physics 2020-02-24 Bálint Koczor , Robert Zeier , Steffen J. Glaser

We apply the generalized Wigner function formalism to detect and characterize a range of quantum phase transitions in several cyclic, finite-length, spin-$\frac{1}{2}$ one-dimensional spin-chain models, viz., the Ising and anisotropic $XY$…

Quantum Physics · Physics 2023-10-03 N. M. Millen , R. P. Rundle , J. H. Samson , Todd Tilma , R. F. Bishop , M. J. Everitt

We present a systematic approach for the semiclassical treatment of many-body dynamics of interacting, open spin systems. Our approach overcomes some of the shortcomings of the recently developed discrete truncated Wigner approximation…

Quantum Physics · Physics 2022-12-01 Christopher D. Mink , David Petrosyan , Michael Fleischhauer

Time reversal and spin flip are discrete symmetry operations of substantial import to quantum information and quantum computation. Spin flip arises in the context of separability, quantification of entanglement and the construction of…

Quantum Physics · Physics 2017-01-18 K. Srinivasan , G. Raghavan

Increasing interest is being dedicated in the last few years to the issues of exact computations and asymptotics of spin networks. The large-entries regimes (semiclassical limits) occur in many areas of physics and chemistry, and in…

Quantum Physics · Physics 2012-11-22 A. C. P. Bitencourt , A. Marzuoli , M. Ragni , R. W. Anderson , V. Aquilanti

We apply the semi-classical limit of the generalized $SO(3)$ map for representation of variable-spin systems in a four-dimensional symplectic manifold and approximate their evolution terms of effective classical dynamics on $T^{\ast…

Density matrix for N-qubit symmetric state or spin-j state (j = N/2) is expressed in terms of the well known Fano statistical tensor parameters. Employing the multiaxial representation [1], wherein a spin-j density matrix is shown to be…

Quantum Physics · Physics 2011-12-09 Swarnamala Sirsi , Veena Adiga

Transition from quantum to semiclassical behaviour and loss of quantum coherence for inhomogeneous perturbations generated from a non-vacuum initial state in the early Universe is considered in the Heisenberg and the Schr\"odinger…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Julien Lesgourgues , David Polarski , Alexei A. Starobinsky

We introduce the notion of $su(2)$ spin-$s$ Dicke states, which are higher-spin generalizations of usual (spin-1/2) Dicke states. These multi-qudit states can be expressed as superpositions of $su(2s+1)$ qudit Dicke states. They satisfy a…

Quantum Physics · Physics 2025-01-28 Rafael I. Nepomechie , Francesco Ravanini , David Raveh

The presence of negative values in the Wigner quasiprobability distribution is deemed one of the hallmarks of nonclassical phenomena in quantum systems. Here we demonstrate a classical model of squeezed light that, when combined with…

Quantum Physics · Physics 2026-01-27 Brian R. La Cour

Non-Gaussian states, and specifically the paradigmatic Schr\"odinger cat state, are well-known to be very sensitive to losses. When propagating through damping channels, these states quickly loose their non-classical features and the…

Quantum Physics · Physics 2018-02-15 H. Le Jeannic , A. Cavaillès , K. Huang , R. Filip , J. Laurat

The symmetric collective states of an atomic spin ensemble (i.e., many-body states that are invariant under particle exchange) are not preserved by decoherence that acts identically but individually on members of the ensemble. We develop a…

Quantum Physics · Physics 2008-05-20 Bradley A. Chase , J. M. Geremia

The subject matter of this work is a 1D quantum spin - $\frac{1}{2}$ chain associated with the inhomogeneous six-vertex model possessing an additional ${\cal Z}_r$ symmetry. The model is studied in a certain parametric domain, where it is…

High Energy Physics - Theory · Physics 2023-07-19 Gleb A. Kotousov , Sergei L. Lukyanov

We define the Wigner entropy of a quantum state as the differential Shannon entropy of the Wigner function of the state. This quantity is properly defined only for states that possess a positive Wigner function, which we name…

Quantum Physics · Physics 2022-01-03 Zacharie Van Herstraeten , Nicolas J. Cerf

We present further progress, in the form of analytical results, on the Wigner entropy conjecture set forth in https://link.aps.org/doi/10.1103/PhysRevA.104.042211 and https://iopscience.iop.org/article/10.1088/1751-8121/aa852f/meta. Said…

Quantum Physics · Physics 2024-08-06 Qipeng Qian , Christos N. Gagatsos