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Related papers: Decoherence and the Final Pointer Basis

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We consider the problem of decoherence and relaxation of open bosonic quantum systems from a perspective alternative to the standard master equation or quantum trajectories approaches. Our method is based on the dynamics of expectation…

Quantum Physics · Physics 2009-11-13 D. A. R. Dalvit , G. P. Berman , M. Vishik

The interaction of a quantum system with its environment causes decoherence, setting a fundamental limit on the suitability of a system for quantum information processing. However, we show that if the quantum system consists of coupled…

Quantum Physics · Physics 2018-04-11 Helen Cammack , Peter Kirton , Paul Eastham , Jonathan Keeling , Brendon Lovett

A perfect quantum state transfer(QST) has been shown in an engineered spin chain with "always-on interaction". Here, we consider a more realistic problem for such a protocol, the quantum decoherence induced by a spatially distributed…

Quantum Physics · Physics 2007-05-23 Lan Zhou , Jing Lu , Tao Shi , C. P. Sun

Coherence is a fundamental resource in quantum information processing, which can be certified by a coherence witness. Due to the imperfection of measurement devices, a conventional coherence witness may lead to fallacious results. We show…

Quantum Physics · Physics 2019-08-30 You-Qi Nie , Hongyi Zhou , Jian-Yu Guan , Qiang Zhang , Xiongfeng Ma , Jun Zhang , Jian-Wei Pan

We analyze the notion of quantum coherence in an interference experiment. We let the phase shifts fluctuate according to a given statistical distribution and introduce a decoherence parameter, defined in terms of a generalized visibility of…

Quantum Physics · Physics 2010-01-31 A. Mariano , P. Facchi , S. Pascazio

The development of quantum walks in the context of quantum computation, as generalisations of random walk techniques, led rapidly to several new quantum algorithms. These all follow unitary quantum evolution, apart from the final…

Quantum Physics · Physics 2008-03-02 Viv Kendon

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

General semiclassical expression for quantum fidelity (Loschmidt echo) of arbitrary pure and mixed states is derived. It expresses fidelity as an interference sum of dephasing trajectories weighed by the Wigner function of the initial…

Quantum Physics · Physics 2007-05-23 Jiri Vanicek

The dynamical evolution of a quantum register of arbitrary length coupled to an environment of arbitrary coherence length is predicted within a relevant model of decoherence. The results are reported for quantum bits (qubits) coupling…

Quantum Physics · Physics 2009-11-07 John H. Reina , Luis Quiroga , Neil F. Johnson

Mapping the system evolution of a two-state system allows the determination of the effective system Hamiltonian directly. We show how this can be achieved even if the system is decohering appreciably over the observation time. A method to…

Recent advances in quantum technology have enabled the simulation of quantum many-body systems on real quantum devices. However, such quantum simulators are inherently subject to decoherence, and its impact on system dynamics - particularly…

Quantum Physics · Physics 2026-02-11 Yuta Hirasaki , Toshinari Itoko , Naoki Kanazawa , Eiji Saitoh

The roles of decoherence and environment-induced superselection in the emergence of the classical from the quantum substrate are described. The stability of correlations between the einselected quantum pointer states and the environment…

Quantum Physics · Physics 2011-08-04 Wojciech H. Zurek

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

Self-interactions and interaction with the environment tend to push quantum systems toward states of maximal entanglement. This is a definition of decoherence. We argue that these maximally entangled states fall into the well-defined…

Quantum Physics · Physics 2022-10-17 Roman V. Buniy , Robert P. Feger , Thomas W. Kephart

Quantum technology resorts to efficient utilization of quantum resources to realize technique innovation. The systems are controlled such that their states follow the desired manners to realize different quantum protocols. However, the…

Quantum Physics · Physics 2021-01-13 Si-Yuan Bai , Chong Chen , Hong Wu , Jun-Hong An

We demonstrate by an explicit model calculation that the decay of entanglement of two two-state systems (two qubits) is governed by the product of the factors that measure the degree of decoherence of each of the qubits, subject to…

Quantum Physics · Physics 2010-10-12 D. Tolkunov , V. Privman , P. K. Aravind

Understanding dissipative and decohering processes is fundamental to the study of quantum systems. An accurate and generic method for investigating these processes is to simulate both the system and environment, which, however, is…

Quantum Physics · Physics 2009-02-21 Michael Zwolak

We present a formulation of the decoherent (or consistent) histories quantum theory of closed systems starting with records of what histories happen. Alternative routes to a formulation of quantum theory like this one can be useful both for…

Quantum Physics · Physics 2016-08-16 James B. Hartle

We study a quantum mechanical toy model that mimics some features of a quenched phase transition. Both by virtue of a time-dependent Hamiltonian or by changing the temperature of the bath we are able to show that even after classicalization…

Quantum Physics · Physics 2009-11-07 Nuno D. Antunes , Fernando C. Lombardo , Diana Monteoliva

In the quantitative theory of quantum coherence, the amount of coherence for given states can be meaningfully discussed only when referring to a preferred basis. One of the objections to this quantification is that the amount of coherence…

Quantum Physics · Physics 2024-12-11 Zhi-Xiang Jin , Yuan-Hong Tao , Bing Yu , Shao-Ming Fei