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Related papers: Evolution equation for quantum coherence

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We study an influence of the continuous measurement in a composite quantum system C on the evolution of the states of its parts. It is shown that the character of the evolution (decoherence or recoherence) depends on the type of the…

Quantum Physics · Physics 2009-11-11 E. D. Vol

Coherence is a defining property of quantum theory that accounts for quantum advantage in many quantum information tasks. Although many coherence quantifiers have been introduced in various contexts, the lack of efficient methods to…

Quantum Physics · Physics 2023-01-02 Sun Liang Liang , Yu Sixia

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

With a choice of boundary conditions for solutions of the Schr\"odinger equation, state vectors and density operators even for closed systems evolve asymmetrically in time. For open systems, standard quantum mechanics consequently predicts…

Quantum Physics · Physics 2010-05-25 P. W. Bryant

W generalize the scheme for detection of qubit-environment entanglement to qudit-environment systems. This is of relevance for many-qubit systems and the quantification of the operation of quantum algorithms under the influence of external…

Quantum Physics · Physics 2025-04-01 Małgorzata Strzałka , Katarzyna Roszak

The theory of decoherence attempts to explain the emergent classical behaviour of a quantum system interacting with its quantum environment. In order to formalize this mechanism we introduce the idea that the information preserved in an…

Quantum Physics · Physics 2008-02-06 Cédric Bény

In the framework of the Lindblad theory for open quantum systems, we determine the degree of quantum decoherence of a harmonic oscillator interacting with a thermal bath. It is found that the system manifests a quantum decoherence which is…

Quantum Physics · Physics 2009-11-13 A. Isar

For the case of phase damping (pure decoherence) we investigate the extent to which environmental traits are imprinted on an open quantum system. The dynamics is described using the quantum channel approach. We study what the knowledge of…

Quantum Physics · Physics 2015-05-20 Julius Helm , Walter T. Strunz , Stephan Rietzler , Lars Erik Würflinger

An initial local excitation in a confined quantum system evolves exploring the whole system, returning to the initial position as a mesoscopic echo at the Heisenberg time. We consider a two weakly coupled spin chains, a spin ladder, where…

The decoherence induced on a single qubit by its interaction with the environment is studied. The environment is modelled as a scalar two-level boson system that can go through either first order or continuous excited state quantum phase…

Quantum Physics · Physics 2015-05-14 P. Perez-Fernandez , A. Relano , J. M. Arias , J. Dukelsky , J. E. Garcia-Ramos

We give a short, critical review of the issue of decoherence. We establish the most general framework in which decoherence can be discussed, how it can be quantified and how it can be measured. We focus on environment induced decoherence…

Quantum Physics · Physics 2016-09-08 Charis Anastopoulos

We found that in contrast with the common premise, a measurement on the environment of an open quantum system can {\em reduce} its decoherence rate. We demonstrate it by studying an example of indirect qubit's measurement, where the…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 Yin Ye , Yunshan Cao , Xin-Qi Li , Shmuel Gurvitz

A simplified Heisenberg spin model is studied in order to examine the idea of decoherence in closed quantum systems. For this purpose, we present a quantifiable definition to quantum coherence $\Xi$, and discuss in some detail a general…

Quantum Physics · Physics 2008-05-18 Olavi Dannenberg

Quantum coherence is a fundamental characteristic to distinguish quantum systems from their classical counterparts. Though quantum coherence persists in isolated non-interacting systems, interactions inevitably lead to decoherence, which is…

Quantum Gases · Physics 2017-11-15 Ke-Ji Chen , Ho Kwan Lau , Hon Ming Chan , Dajun Wang , Qi Zhou

We establish a lower bound on the quantum coherence of an arbitrary quantum state in arbitrary dimension, using a noncommutativity estimator of an arbitrary observable of sub-unit norm, where the estimator is the commutator of the…

Quantum Physics · Physics 2022-06-22 Tanaya Ray , Ahana Ghoshal , Arun Kumar Pati , Ujjwal Sen

A key lesson of the decoherence program is that information flowing out from an open system is stored in the quantum state of the surroundings. Simultaneously, quantum measurement theory shows that the evolution of any open system when its…

Quantum Physics · Physics 2012-01-27 Juan Diego Urbina , Walter T. Strunz , Carlos Viviescas

The effect of decoherence, induced by spontaneous emission, on the dynamics of cold atoms periodically kicked by an optical lattice is experimentally and theoretically studied. Ideally, the mean energy growth is essentially unaffected by…

Quantum coherence is a fundamental property of quantum systems, separating quantum from classical physics. Recently, there has been significant interest in the characterization of quantum coherence as a resource, investigating how coherence…

We show that quantum properties of spacetime, encoded by noncommutativity at the Planck scale, lead to a generalized time evolution of quantum systems in which pure states can evolve into mixed states. Specifically, a decoherence mechanism…

General Relativity and Quantum Cosmology · Physics 2023-01-27 Michele Arzano , Vittorio D'Esposito , Giulia Gubitosi

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