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Related papers: Quantum Decoherence of Two Qubits

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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

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

We study a model of dephasing (decoherence) in a two-state quantum system (qubit) coupled to a bath of harmonic oscillators. An exact analytic solution for the reduced dynamics of a two-state system in this model has been obtained…

Quantum Physics · Physics 2015-05-28 V. G. Morozov , S. Mathey , G. Röpke

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

Quantum decoherence has been studied using nuclear magnetic resonance(NMR). By choosing one qubit to simulate environment, we examine the decoherence behavior of two quantum systems: a one qubit system and a two qubit system. The…

Quantum Physics · Physics 2007-05-23 Jingfu Zhang , Zhiheng Lu , Lu Shan , Zhiwei Deng

Symmetry implications for the decoherence of quantum oscillations of a two-state system in a solid are studied. When the oscillation frequency is small compared to the Debye frequency, the universal lower bound on the decoherence due to the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Eugene M. Chudnovsky

We study one-way quantum deficit of two-qubit $X$ states systematically from analytical derivations. An effective approach to compute one-way quantum deficit of two-qubit $X$ states has been provided. Analytical results are presented as for…

Quantum Physics · Physics 2016-03-15 Biao-Liang Ye , Yao-Kun Wang , Shao-Ming Fei

Quantum decoherence, which appears when a system interacts with its environment in an irreversible way, plays a fundamental role in the description of quantum-to-classical transitions and has been successfully applied in some important…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Jieci Wang , Jiliang Jing

The effects of fluctuating boundaries on a superposition state of a quantum particle in a box is studied. We consider a model in one space dimension in which the initial state is a coherent superposition of two energy eigenstates. The…

Quantum Physics · Physics 2012-05-11 V. A. De Lorenci , L. H. Ford

Decoherence of quantum states is a major hurdle towards scalable and reliable quantum computing. Lower decoherence (i.e., higher fidelity) can alleviate the error correction overhead and obviate the need for energy-intensive noise reduction…

Emerging Technologies · Computer Science 2019-04-10 Abdullah Ash Saki , Mahabubul Alam , Swaroop Ghosh

The problem investigated in this paper is einselection, i. e. the selection of mutually exclusive quantum states with definite probabilities through decoherence. Its study is based on a theory of decoherence resulting from the projection…

Quantum Physics · Physics 2009-11-10 Roland Omnes

It is commonly believed that decoherence arises as a result of the entangling interaction between a quantum system and its environment, as a consequence of which the environment effectively measures the system, thus washing away its quantum…

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

We show that it is possible to explain the quantum measurement process within the framework of quantum mechanics without any additional postulates. The key concept of the theory is decoherence, which appears as an inherent characteristic of…

General Physics · Physics 2019-11-01 Riuji Mochizuki

In this paper, we analyze the evolution of quantum coherence in a two-qubit system going through the amplitude damping channel. After they have gone through this channel many times, we analyze the systems with respect to the coherence of…

Quantum Physics · Physics 2017-12-29 Ming-Jing Zhao , Teng Ma , YuQuan Ma

We study decoherence of one, two, and $n$ non-interacting qubits. Decoherence, measured in terms of purity, is calculated in linear response approximation, making use of the spectator configuration. The environment and its interaction with…

Quantum Physics · Physics 2007-11-30 Carlos Pineda

Quantum discord is a more general measure of quantum correlations than entanglement and has been proposed as a resource in certain quantum information processing tasks. The computation of discord is mostly confined to two-qubit systems for…

Quantum Physics · Physics 2015-06-05 Indrani Bose , Amit Kumar Pal

Cooperative effects in the loss (the amplitude damping) and decoherence (the phase damping) of the qubits (two-state quantum systems) due to the inevitable coupling to the same environment are investigated. It is found that the qubits…

Quantum Physics · Physics 2007-05-23 Lu-Ming Duan , Guang-Can Guo

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

An alternative approach to decoherence, named non-dynamical decoherence is developed and used to resolve the quantum measurement problem. According to decoherence, the observed system is open to a macroscopic apparatus(together with a…

Quantum Physics · Physics 2015-04-08 Yu-Lei Feng , Yi-Xin Chen