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Related papers: Disturbance-Based Measure of Macroscopic Coherence

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Based on phase-space structures of quantum states, we propose a novel measure to quantify macroscopic quantum superpositions. Our measure simultaneously quantifies two different kinds of essential information for a given quantum state in a…

Quantum Physics · Physics 2011-06-02 Chang-Woo Lee , Hyunseok Jeong

We develop a rigorous connection between statistical properties of an interference pattern and the coherence properties of the underlying quantum state. With explicit examples, we demonstrate that even for inaccurate reconstructions of…

Quantum Physics · Physics 2015-11-25 Kai von Prillwitz , Łukasz Rudnicki , Florian Mintert

We consider realistic measurement systems, where measurements are accompanied by decoherence processes. The aim of this work is the construction of methods and algorithms for precise quantum measurements with fidelity close to the…

Quantum Physics · Physics 2017-01-10 Yu. I. Bogdanov , B. I. Bantysh , N. A. Bogdanova , A. B. Kvasnyy , V. F. Lukichev

Weak measurements cause small change to quantum states, thereby opening up the possibility of new ways of manipulating and controlling quantum systems. We ask, can weak measurements reveal more quantum correlation in a composite quantum…

Quantum Physics · Physics 2014-06-12 Uttam Singh , Arun Kumar Pati

It is difficult to evaluate the precision of quantum measurements because it is not possible to conduct a second reference measurement on the same physical system to compare the measurement outcome with a more accurate value of the measured…

Quantum Physics · Physics 2021-02-10 Holger F. Hofmann

Several ways have been proposed in the literature to define a coherence measure based on Tsallis relative entropy. One of them is defined as a distance between a state and a set of incoherent states with Tsallis relative entropy taken as a…

Quantum Physics · Physics 2019-12-12 Anna Vershynina

In order to understand quantum decoherence of a quantum system due to its interaction with a large system behaving classically, we introduce the concept of adiabatic quantum entanglement based on the Born-Oppenhemeir approximation. In the…

Quantum Physics · Physics 2019-08-17 C. P. Sun , D. L. Zhou , S. Yu , X. F. Liu

We introduce information-theoretic definitions for noise and disturbance in quantum measurements and prove a state-independent noise-disturbance tradeoff relation that these quantities have to satisfy in any conceivable setup. Contrary to…

Quantum Physics · Physics 2014-07-29 Francesco Buscemi , Michael J. W. Hall , Masanao Ozawa , Mark M. Wilde

In this paper, by minimizing the coherence quantifiers over all states in an $\epsilon$ ball around a given state, we define a generalized smooth quantifier, called the $\epsilon$-smooth measure of coherence. We use it to estimate the…

Quantum Physics · Physics 2019-01-16 Zhengjun Xi , Shanshan Yuwen

In quantum information theory, quantum discord has been proposed as a tool to characterise the presence of "quantum correlations" between the subparts of a given system. Whether a system behaves quantum-mechanically or classically is…

Quantum Physics · Physics 2022-10-20 Jerome Martin , Amaury Micheli , Vincent Vennin

Quantum decoherence can arise due to classical fluctuations in the parameters which define the dynamics of the system. In this case decoherence, and complementary noise, is manifest when data from repeated measurement trials are combined.…

General Relativity and Quantum Cosmology · Physics 2011-09-13 G. J. Milburn

The quantification of quantum coherence has attracted a growing attention, and based on various physical contexts, several coherence measures have been put forward. An interesting question is whether these coherence measures give the same…

Quantum Physics · Physics 2016-09-20 C. L. Liu , Xiao-Dong Yu , G. F. Xu , D. M. Tong

The standard quantum coherence theory is defined with respect to an orthonormal basis of a Hilbert space. Recently, Bischof, Kampermann and Bru% \ss\ generalized the notion of coherence into the case of general measurements, and also, they…

Quantum Physics · Physics 2021-07-23 Jianwei Xu

In 1927, Heisenberg heuristically disclosed the tradeoff between the error in the measurement and the caused disturbance on another complementary observable. In the quantum theory, most of uncertainty relations are proposed to reveal the…

Quantum Physics · Physics 2014-10-29 Li-Yi Hsu

Quantum decoherence arises due to uncontrollable entanglement between a system with its environment. However the effects of decoherence are often thought of and modeled through a simpler picture in which the role of the environment is to…

Quantum Physics · Physics 2019-09-17 Bing Gu , Ignacio Franco

In this paper we introduce a simple procedure for computing the macroscopic quantum behaviour of periodic quantum systems in the high energy regime. The macroscopic quantum coherence is ascribed to a one-particle state, not to a condensate…

Quantum Physics · Physics 2015-06-17 A. Martín-Ruiz , J. Bernal , Adrián Carbajal-Domínguez

In an idealistic setting, quantum metrology protocols allow to sense physical parameters with mean squared error that scales as $1/N^2$ with the number of particles involved---substantially surpassing the $1/N$-scaling characteristic to…

Quantum Physics · Physics 2015-01-05 Jan Kolodynski

Quantum coherence is the basic concept of superposition of quantum states and plays an important role in quantum metrology. We show how a pair of uniformly accelerated observers with a local two-mode Gaussian quantum state affects the…

Quantum Physics · Physics 2023-04-18 Xiaolong Gong , Yue Fang , Tonghua Liu , Shuo Cao

We investigate the maximally coherent states to provide a refinement in quantifying coherence and give a measure-independent definition of the coherence-preserving operations. A maximally coherent state can be considered as the resource to…

Quantum Physics · Physics 2016-03-22 Yi Peng , Yong Jiang , Heng Fan

We present a generic structure (the layer structure) for decoherence effects in neutrino oscillations, which includes decoherence from quantum mechanical and classical uncertainties. The calculation is done by combining the concept of open…

High Energy Physics - Phenomenology · Physics 2022-08-24 Ting Cheng , Manfred Lindner , Werner Rodejohann