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Related papers: Decoherence-Free Subspaces and Subsystems

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An algebraic formalism for quantum decoherence in systems with continuous evolution spectrum is introduced. A certain subalgebra, dense in the characteristic algebra of the system, is defined in such a way that Riemann-Lebesgue theorem can…

Mathematical Physics · Physics 2019-08-17 M. A. Castagnino , A. R. Ordoniez

Quantum states are described by wave functions whose phases cannot be directly measured, but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence,…

Chemical Physics · Physics 2019-12-20 Jia Chen , Cong Hu , John F. Stanton , Stephen Hill , Hai-Ping Cheng , Xiao-Guang Zhang

Coherent interaction of a quantum system with environment usually induces quantum decoherence. However, remarkably, in certain configurations the coherent system-environment coupling can be simultaneously explored to engineer a specific…

Within the decoherence theory we investigate the physical background of the condition of the separability (diagonalizability in noncorrelated basis) of the interaction Hamiltonian of the composite system, "system plus environment". It…

Quantum Physics · Physics 2007-05-23 M. Dugic

We present a detailed report on the decoherence of quantum states of continuous variable systems under the action of a quantum optical master equation resulting from the interaction with general Gaussian uncorrelated environments. The rate…

Quantum Physics · Physics 2007-05-23 A. Serafini , M. G. A. Paris , F. Illuminati , S. De Siena

We study the decoherence induced by the environment over a composite quantum system, comprising two coupled subsystems A and B, which may be a harmonic or an upside-down oscillators. We analyze the case in which the B-subsystem is in direct…

Quantum Physics · Physics 2009-11-11 Fernando C. Lombardo , Paula I. Villar

A small quantum system is studied which is a superposition of states localized in different positions in a static gravitational field. The time evolution of the correlation between different positions is investigated, and it is seen that…

Quantum Physics · Physics 2016-10-11 Ahmad Shariati , Mohammad Khorrami , Farhang Loran

We explore a strategy for protecting the evolution of a qubit against the effects of environmental noise based on the application of controlled time-dependent perturbations. In the case of a purely decohering coupling, an explicit sequence…

Quantum Physics · Physics 2007-05-23 Lorenza Viola , Seth Lloyd

We present a rigorous analysis of the phenomenon of decoherence for general $N-$level systems coupled to reservoirs. The latter are described by free massless bosonic fields. We apply our general results to the specific cases of the qubit…

Quantum Physics · Physics 2009-11-13 M. Merkli , I. M. Sigal , G. P. Berman

It is shown that a nonequilibrium environment can be instrumental in suppressing decoherence between distinct decoherence free subspaces in quantum registers. The effect is found in the framework of exact coherent-product solutions for…

Quantum Physics · Physics 2009-11-07 S. Gheorghiu-Svirschevski

Usually, decoherence is generated from the coupling with an outer environment. However, a macroscopic object generically possesses its own environment in itself, namely the complicated dynamics of internal degrees of freedom. We address a…

Quantum Physics · Physics 2007-05-23 Sang Wook Kim , Hwa-Kyun Park

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

Decoherence of a quantum system (which then starts to display classical features) results from the interaction of the system with the environment, and is well described in the framework of the theory of continuous quantum measurements…

Quantum Physics · Physics 2010-12-17 Michael B. Mensky

Different approaches in quantifying environmentally-induced decoherence are considered. We identify a measure of decoherence, derived from the density matrix of the system of interest, that quantifies the environmentally induced error,…

Mesoscale and Nanoscale Physics · Physics 2010-10-12 Arkady Fedorov , Leonid Fedichkin , Vladimir Privman

Decoherence is widely felt to have something to do with the quantum measurement problem, but getting clear on just what is made difficult by the fact that the "measurement problem", as traditionally presented in foundational and…

Quantum Physics · Physics 2015-06-03 David Wallace

Decoherence-Free Subsystems (DFS) are a powerful means of protecting quantum information against noise with known symmetry properties. Although Hamiltonians theoretically exist that can implement a universal set of logic gates on DFS…

Quantum Physics · Physics 2007-05-23 P. Cappellaro , J. S. Hodges , T. F. Havel , D. G. Cory

The destruction of quantum interference, decoherence, and the destruction of entanglement both appear to occur under the same circumstances. To address the connection between these two phenomena, we consider the evolution of arbitrary…

Quantum Physics · Physics 2009-11-10 P. J. Dodd , J. J. Halliwell

Unitarity is a pillar of quantum theory. Nevertheless, it is also a source of several of its conceptual problems. We note that in a world where measurements are relational, as is the case in gravitation, quantum mechanics exhibits a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rodolfo Gambini , Rafael Porto , Jorge Pullin

The fact that the Environment Induced Decoherence approach offers no general criterion to decide where to place the "cut" between system and environment has been considered as a serious conceptual problem of the proposal. In this letter we…

Quantum Physics · Physics 2010-02-23 Mario Castagnino , Sebastian Fortin , Olimpia Lombardi

The decoherence phenomenon arising from an environmental monitoring of the state of a quantum system, as opposed to monitoring of a preferred observable, is worked out in detail using two equivalent formulations, namely, repeated…

Quantum Physics · Physics 2026-03-17 Dorje C. Brody , Rishindra Melanathuru