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I investigate the decoherence of two-mode squeezed vacuum states by analyzing the relative entropy of entanglement. I consider two sources of decoherence: (i) the phase damping and (ii) the amplitude damping due to the coupling to the…

Quantum Physics · Physics 2009-11-06 Tohya Hiroshima

We study the entanglement properties of randomized mixed hypergraph states, extending the concept of randomized mixed graph states to encompass hypergraph-based quantum states. In our model, imperfect generalized multi-qubit gates are…

Quantum Physics · Physics 2026-04-13 Vinícius Salem , Alison A. Silva , Fabiano M. Andrade

We investigate the dynamics for a two level atomic system entangled to coherent states using the recently developed mode invisibility technique. Using a quantum 2-level probe, we demonstrate a way to non-destructively measure a number of…

Quantum Physics · Physics 2017-10-04 Paulina Corona-Ugalde , Marvellous Onuma-Kalu , Robert B. Mann

Inspired by ER=EPR conjecture we present a mathematical tool providing a link between quantum entanglement and the geometry of spacetime. We start with the idea of operators in extended Hilbert space which, by definition, has no positive…

High Energy Physics - Theory · Physics 2019-08-30 Grzegorz Plewa

Entanglement entropy provides a powerful characterization of two-dimensional gapped topological phases of quantum matter, intimately tied to their description by topological quantum field theories (TQFTs). Fracton topological orders are…

Strongly Correlated Electrons · Physics 2018-03-08 Han Ma , A. T. Schmitz , S. A. Parameswaran , Michael Hermele , Rahul M. Nandkishore

Modeling the qubit by a two-level semiclassical detector coupled to a massless scalar field, we investigate how the Unruh effect affects the nonlocality and entanglement of two-qubit and three-qubit states when one of the entangled qubits…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Zehua Tian , Jieci Wang , Jiliang Jing

We approach the physical implications of the non-commutative nature of Complementary Observable Algebras (COA) from an information theoretic perspective. In particular, we derive a general \textit{entropic certainty principle} stating that…

High Energy Physics - Theory · Physics 2021-01-20 Javier M. Magan , Diego Pontello

We give a direct alternative proof of an area law for the entanglement entropy of the ground state of disordered oscillator systems---a result due to Nachtergaele, Sims and Stolz. Instead of studying the logarithmic negativity, we invoke…

Mathematical Physics · Physics 2019-10-11 Vincent Beaud , Julian Sieber , Simone Warzel

Density matrices are the most general descriptions of quantum states, covering both pure and mixed states. Positive semidefiniteness is a physical requirement of density matrices, imposing nonnegative probabilities of measuring physical…

Quantum Physics · Physics 2024-09-11 Colm Kelleher

This work is an enquiry into the circumstances under which entropy methods can give an answer to the questions of both quantum separability and classical correlations of a composite state. Several entropy functionals are employed to examine…

Quantum Physics · Physics 2009-11-07 A. K. Rajagopal , R. W. Rendell

We consider reflected entropy in a thermofield double state perturbed by a heavy operator insertion. For sufficiently early operator insertions the dual geometry can be described by a localized shock wave geometry. We calculate the…

High Energy Physics - Theory · Physics 2020-08-11 Jan Boruch

In this paper, we follow our presented model in J. Opt. Soc. Am. B {\bf 30}, 1109--1117 (2013), in which the interaction between a $\Lambda$-type three-level atom and a quantized two-mode radiation field in a cavity in the presence of…

Quantum Physics · Physics 2014-07-29 M J Faghihi , M K Tavassoly

We study the logarithmic negativity and the moments of the partial transpose in the ground state of a two dimensional massless harmonic square lattice with nearest neighbour interactions for various configurations of adjacent domains. At…

Statistical Mechanics · Physics 2017-04-20 Cristiano De Nobili , Andrea Coser , Erik Tonni

In this paper we study the effect of non-trivial spatial topology on quantum entanglement by examining the degenerate ground states of a topologically ordered system on torus. Using the string-net (fixed-point) wave-function, we propose a…

Strongly Correlated Electrons · Physics 2016-08-17 Zhu-Xi Luo , Yu-Ting Hu , Yong-Shi Wu

In this manuscript we study the behaviour of the entanglement measure dubbed negativity in the context of the toric code model. Using a method introduced recently by Calabrese, Cardy and Tonni [Phys. Rev. Lett. 109, 130502 (2012)], we…

Strongly Correlated Electrons · Physics 2014-01-30 Claudio Castelnovo

Quantum nonlocality is tested for an entangled coherent state, interacting with a dissipative environment. A pure entangled coherent state violates Bell's inequality regardless of its coherent amplitude. The higher the initial nonlocality,…

Quantum Physics · Physics 2009-11-07 D. Wilson , H. Jeong , M. S. Kim

We explore properties of the universal terms in the entanglement entropy and logarithmic negativity in 4d CFTs, aiming to clarify the ways in which they behave like the analogous entanglement measures in quantum mechanics. We show that,…

High Energy Physics - Theory · Physics 2015-10-28 Eric Perlmutter , Mukund Rangamani , Massimiliano Rota

In this report we consider the three dimensional subset of the space of states of two qubits that may be written in the so called standard form. For those states we show that different measures of entanglement, specifically concurrence,…

Quantum Physics · Physics 2007-12-07 D. Mundarain , J. Stephany

We elucidate the topological features of the entanglement entropy of a region in two dimensional quantum systems in a topological phase with a finite correlation length $\xi$. Firstly, we suggest that simpler reduced quantities, related to…

Strongly Correlated Electrons · Physics 2009-11-13 Stefanos Papanikolaou , Kumar S. Raman , Eduardo Fradkin

In quantum theory, physical amplitudes are usually presented in the form of Feynman perturbation series in powers of coupling constant $\al .$ However, it is known that these amplitudes are not regular functions at $\alpha=0 .$ For QCD, we…

High Energy Physics - Phenomenology · Physics 2008-12-18 D. V. Shirkov