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Related papers: Discord and Decoherence

200 papers

Understanding the emergence of classical behavior from a quantum theory is vital to establishing the quantum origin for the temperature fluctuations observed in the Cosmic Microwave Background (CMB). We show that a real-space approach can…

General Relativity and Quantum Cosmology · Physics 2024-02-12 S. Mahesh Chandran , Karthik Rajeev , S. Shankaranarayanan

Quantum discord has been studied extensively as a measure of non-classical correlations which includes entanglement as a subset. Although it is well known that non-zero discord can exist without entanglement, the origin of quantum discord…

Quantum Physics · Physics 2017-08-02 Yu Guo , Sumit Goswami

We analyze the interplay of chaos, entanglement and decoherence in a system of qubits whose collective behaviour is that of a quantum kicked top. The dynamical entanglement between a single qubit and the rest can be calculated from the mean…

Quantum Physics · Physics 2009-11-13 S. Ghose , R. Stock , P. S. Jessen , R. Lal , A. Silberfarb

Decoherence induced by coupling a system with an environment may display universal features. Here we demostrate that when the coupling to the system drives a quantum phase transition in the environment, the temporal decay of quantum…

Quantum Physics · Physics 2007-05-23 Fernando Martin Cucchietti , Sonia Fernandez-Vidal , Juan Pablo Paz

This paper examines the coherence in multipartite systems. We first discuss the distribution of total coherence in a given multipartite quantum state into discord between subsystems and coherent dissonance in each individual subsystem,…

Quantum Physics · Physics 2018-09-26 Zhengjun Xi

The spurious interaction of quantum systems with their environment known as decoherence leads, as a function of time, to a decay of coherence of superposition states. Since the interactions between system and environment are local, they can…

Quantum Physics · Physics 2015-03-19 Gonzalo A. Alvarez , Dieter Suter

Quantum discord, a measure of genuinely quantum correlations, is generalized to continuous variable systems. For all two-mode Gaussian states, we calculate analytically the quantum discord and a related measure of classical correlations,…

Quantum Physics · Physics 2015-03-13 Gerardo Adesso , Animesh Datta

Criteria of measure quantifying quantum coherence, a unique property of quantum system, are proposed recently. In this paper, we first give an uncertainty-like expression relating the coherence and the entropy of quantum system. This…

Quantum Physics · Physics 2015-07-15 Zhengjun Xi , Yongming Li , Heng Fan

In this work, we investigate the dynamics of quantum correlations captured by entropic and geometric measures of discord under the influence of dissipative channels for widely used two qubit X state with maximally mixed marginals.…

Quantum Physics · Physics 2022-05-31 Nitish Kumar Chandra , Sarang S. Bhosale , Prasanta K. Panigrahi

It is known that a macroscopic quantum superposition (MQS), when it is exposed to environment, decoheres at a rate scaling with the separation of its component states in phase space. This is more or less consistent with the well known…

Quantum Physics · Physics 2009-11-13 Hyunseok Jeong , Jinhyoung Lee , Hyunchul Nha

It is well known that many operations in quantum information processing depend largely on a special kind of quantum correlation, that is, entanglement. However, there are also quantum tasks that display the quantum advantage without…

Quantum Physics · Physics 2015-05-14 Jin-Shi Xu , Xiao-Ye Xu , Chuan-Feng Li , Cheng-Jie Zhang , Xu-Bo Zou , Guang-Can Guo

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 2019-09-04 Matthew A. Hunt , Igor V. Lerner , Igor V. Yurkevich , Yuval Gefen

We study the evolution of quantum correlations, quantified by the geometric discord, of two excitonic quantum dot qubits under the influence of the phonon environment. We show that the decay of these correlations differs substantially form…

Quantum Physics · Physics 2013-11-11 Katarzyna Roszak , Paweł Mazurek , Paweł Horodecki

The destruction of quantum coherence by environmental influences is investigated taking the damped harmonic oscillator and the dissipative two-state system as prototypical examples. It is shown that the location of the coherent-incoherent…

Statistical Mechanics · Physics 2009-10-30 Reinhold Egger , Hermann Grabert , Ulrich Weiss

Spin qubits are at the heart of technological advances in quantum processors and offer an excellent framework for quantum information processing. This work characterizes the time evolution of coherence and nonclassical correlations in a…

Quantum Physics · Physics 2023-04-13 Zakaria Dahbi , Mansoura Oumennana , Mostafa Mansour

We investigate how decoherence affects the short-time separation between quantum and classical dynamics for classically chaotic systems, within the framework of a specific model. For a wide range of parameters, the distance between the…

Quantum Physics · Physics 2009-11-10 F. Toscano , R. L. de Matos Filho , L. Davidovich

Decoherence is an essential mechanism that defines the boundary between classical and quantum behaviours, while imposing technological bounds for quantum devices. Little is known about quantum coherence of mechanical systems, as opposed to…

Mesoscale and Nanoscale Physics · Physics 2017-10-26 Olivier Maillet , Frantisek Vavrek , Andrew D. Fefferman , Olivier Bourgeois , Eddy Collin

We describe the decoherence process induced on a two-level quantum system in direct interaction with a non-equilibrium environment. The non-equilibrium feature is represented by a non-stationary random function corresponding to the…

Quantum Physics · Physics 2015-06-15 Fernando C. Lombardo , Paula I. Villar

Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of…

Quantum Physics · Physics 2015-11-04 Davide Girolami

We study the decoherence of a quantum computer in an environment which is inherently correlated in time and space. We first derive the nonunitary time evolution of the computer and environment in the presence of a stabilizer error…

Quantum Physics · Physics 2007-05-23 E. Novais , Harold U. Baranger