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Related papers: Entanglement and discord in two-mode Gaussian open…

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Gaussian quantum discord is a measure of quantum correlations in Gaussian systems. Using Gaussian discord we quantify the quantum correlations of a bipartite entangled state and a separable two-mode mixture of coherent states. We…

Quantum Physics · Physics 2012-08-13 Lars S. Madsen , Adriano Berni , Mikael Lassen , Ulrik L. Andersen

Dynamics of an open two-qubit system is investigated in the post-Markovian regime, where the environments have a short-term memory. Each qubit is coupled to separate environment which is held in its own temperature. The inter-qubit…

Quantum Physics · Physics 2016-04-28 Hamidreza Mohammadi

In the framework of the theory of open systems based on completely positive quantum dynamical semigroups, we give a description of continuous variable Gaussian R\'enyi-2 (GR2) quantum discord for a system consisting of two non-interacting…

Quantum Physics · Physics 2015-06-12 Aurelian Isar

We study two two-level atomic quantum systems (qubits) placed close to a body held at a temperature different from that of the surrounding walls. While at thermal equilibrium the two-qubit dynamics is characterized by not entangled steady…

Quantum Physics · Physics 2015-09-01 Bruno Bellomo , Mauro Antezza

We show that a bipartite Gaussian quantum system interacting with an external Gaussian environment may possess a unique Gaussian entangled stationary state and that any initial state converges towards this stationary state. We discuss…

Quantum Physics · Physics 2024-07-22 A. Dhahri , F. Fagnola , D. Poletti , H. J. Yoo

The decoherence of quantum correlation is investigated in the Heisenberg spin system with the asymmetric anisotropic interactions. The quantum entanglement and discord are used to quantify the quantumness of the correlations. By the…

Quantum Physics · Physics 2012-08-09 Xiang Hao , Chunlan Ma , Jinqiao Sha

We analytically exploit the two-mode Gaussian states nonunitary dynamics. We show that in the zero temperature limit, entanglement sudden death (ESD) will always occur for symmetric states (where initial single mode compression is $z_0$)…

Quantum Physics · Physics 2015-03-20 L. A. M. Souza , R. C. Drumond , M. C. Nemes , K. M. Fonseca Romero

In recent years the paradigm based on entanglement as the unique measure of quantum correlations has been challenged by the rise of new correlation concepts, such as quantum discord, able to reveal quantum correlations that are present in…

Quantum Physics · Physics 2013-05-30 Paolo Giorda , Michele Allegra , Matteo G. A. Paris

We analyze the evolution of the Gaussian discord between two resonant harmonic oscillators coupled to a common environment. For this, we use the same tools we applied before to fully characterize the evolution of the entanglement in this…

Quantum Physics · Physics 2012-03-20 José Nahuel Freitas , Juan Pablo Paz

We calculate the dissipative dynamics of two-qubit quantum discord under Markovian environments. We analyze various dissipative channels such as dephasing, depolarizing, and generalized amplitude damping, assuming independent perturbation,…

Quantum Physics · Physics 2009-09-16 T. Werlang , S. Souza , F. F. Fanchini , C. J. Villas-Boas

Quantum correlations between parts of a composite system most clearly reveal themselves through entanglement. Designing, maintaining, and controlling entangled systems is very demanding, which raises the stakes for understanding the…

Quantum Physics · Physics 2019-08-21 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

We discover a new class of Gaussian bound entangled states of four-mode continuous-variable systems. These states appear as a transient phase when certain NPT-entangled Gaussian states are evolved under a noisy environment. A thermal bath…

Quantum Physics · Physics 2026-05-12 Gurvir Singh , Saptarshi Roy , Arvind

The entanglement criterion for continuous variable systems and the conditions under which the uncertainty relations are fulfilled are generalized to the case of a noncommutative (NC) phase-space. The quantum nature and the separability of…

Quantum correlations in multiple quantum (MQ) NMR experiments are investigated in two-spin systems (dimers). In the initial moment of time one spin is in a pure quantum polarized state and the other spin is in the thermodynamic equilibrium…

Quantum Physics · Physics 2017-01-16 S. A. Gerasev , E. I. Kuznetsova

We show that quantum mechanical entanglement can prevail even in noisy open quantum systems at high temperature and far from thermodynamical equilibrium, despite the deteriorating effect of decoherence. The system consists of a number N of…

Quantum Physics · Physics 2007-05-23 L. Hartmann , W. Dür , H. -J. Briegel

We consider an open quantum system of N not directly interacting spins (qubits) in contact with both local and collective thermal environments. The qubit-environment interactions are energy conserving. We trace out the variables of the…

Quantum Physics · Physics 2011-09-13 M. Merkli , G. P. Berman , F. Borgonovi , V. I. Tsifrinovic

The dynamics of entanglement and quantum discord for qubit-qutrit systems are studied in the presence of phase damping and amplitude damping noises. Both one way and two couplings of the marginal systems with the environments are…

Quantum Physics · Physics 2016-12-22 Salman Khan , Ishaq Ahmad

Quantum correlation is a key component in various quantum information processing tasks. Decoherence process imposes limitations on achieving these quantum tasks. Therefore, understanding the behavior of quantum correlations in…

Quantum Physics · Physics 2025-01-14 Jamal El Qars

We investigate the dynamical evolution of quantum discord, entanglement and purity in an open quantum system of two coupled asymmetric harmonic oscillators interacting with a thermal environment. Using the Kossakowski-Lindblad master…

Quantum Physics · Physics 2026-03-25 Somayeh Mehrabankar , Farkhondeh Abbasnezhad , Davood Afshar , Aurelian Isar

Quantumness and separability criteria for continuous variable systems are discussed for the case of a noncommutative (NC) phase-space. In particular, the quantum nature and the entanglement configuration of NC two-mode Gaussian states are…

Quantum Physics · Physics 2015-10-13 Alex E. Bernardini , Catarina Bastos , Orfeu Bertolami , Nuno C. Dias , João N. Prata