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Related papers: Quantifying coherence of quantum measurements

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Quantum measurement is a fundamental concept in the field of quantum mechanics. The action of quantum measurement, leading the superposition state of the measured quantum system into a definite output state, not only reconciles…

General Physics · Physics 2024-08-13 Wei Wen

In recent years, several measures have been proposed for characterizing the coherence of a given quantum state. We derive several results that illuminate how these measures behave when restricted to pure states. Notably, we present an…

Quantum Physics · Physics 2016-10-26 Jianxin Chen , Shane Grogan , Nathaniel Johnston , Chi-Kwong Li , Sarah Plosker

Quantum metrology concerns improving the estimation of an unknown parameter using an optimal measurement scheme on the quantum system. More the optimality of the measurement, the better will be the improvement in sensing the value of the…

Quantum Physics · Physics 2025-07-30 H. S. Karthik

Quantum states and measurements exhibit wave-like --- continuous, or particle-like --- discrete, character. Hybrid discrete-continuous photonic systems are key to investigating fundamental quantum phenomena, generating superpositions of…

We introduce the concept of degree of quantumness in quantum synchronization, a measure of the quantum nature of synchronization in quantum systems. Following techniques from quantum information, we propose the number of non-commuting…

Quantum Physics · Physics 2020-01-06 H. Eneriz , D. Z. Rossatto , F. A. Cárdenas-L'opez , E. Solano , M. Sanz

Quantum resource theories provide a diverse and powerful framework for extensively studying the phenomena in quantum physics. Quantum coherence, a quantum resource, is the basic ingredient in many quantum information tasks. It is a subject…

Quantum Physics · Physics 2021-05-19 Sunho Kim , Chunhe Xiong , Asutosh Kumar , Junde Wu

We mainly study the block-coherence measures based on resource theory of block-coherence and the coherence measures based on positive-operator-valued measures (POVM). Several block-coherence measures including a block-coherence measure…

Quantum Physics · Physics 2022-11-23 Liangxue Fu , Fengli Yan , Ting Gao

Quantifying coherence has received increasing attention, and considerable work has been directed towards finding coherence measures. While various coherence measures have been proposed in theory, an important issue following is how to…

Quantum Physics · Physics 2018-05-02 Da-Jian Zhang , C. L. Liu , Xiao-Dong Yu , D. M. Tong

Quantifying coherence and entanglement is extremely important in quantum information processing. Here, we present numerical and analytical results for the geometric measure of coherence, and also present numerical results for the geometric…

Quantum Physics · Physics 2020-08-27 Zhou Zhang , Yue Dai , Yuli Dong , Chengjie Zhang

In this paper we introduce a measure of genuine quantum incompatibility in the estimation task of multiple parameters, that has a geometric character and is backed by a clear operational interpretation. This measure is then applied to some…

Quantum Physics · Physics 2021-06-22 Federico Belliardo , Vittorio Giovannetti

Quantum chemistry is among the most promising applications of quantum computing, offering the potential to solve complex electronic structure problems more efficiently than classical approaches. A critical component of any quantum algorithm…

Quantum Physics · Physics 2025-06-02 Smik Patel , Praveen Jayakumar , Tzu-Ching Yen , Artur F. Izmaylov

The measurement process in quantum mechanics is usually described by the von Neumann projection postulate, which forms a basic constituent of the laws of quantum mechanics. Since this postulate requires the outside observer of the system,…

Quantum Physics · Physics 2009-11-11 Masahiro Morikawa , Akika Nakamichi

We provide a coherence-based approach to nonclassical behavior by means of distance measures. We develop a quantitative relation between coherence and nonclassicality quantifiers, which establish the nonclassicality as the maximum…

Quantum Physics · Physics 2022-07-20 Laura Ares , Alfredo Luis

Quantum coherence is a fundamental manifestation of the quantum superposition principle. Recently, Baumgratz \emph{et al}. [Phys. Rev. Lett. \textbf{113}, 140401 (2014)] presented a rigorous framework to quantify coherence from the view of…

Quantum Physics · Physics 2017-08-02 Xianfei Qi , Ting Gao , Fengli Yan

It is well known that a quantum correlated probe can yield better precision in estimating an unknown parameter than classically possible. However, how such a quantum probe should be measured remains somewhat elusive. We examine the role of…

Quantum Physics · Physics 2015-02-20 K. Micadei , D. A. Rowlands , F. A. Pollock , L. C. Céleri , R. M. Serra , K. Modi

A pedagogical and reasonably self-contained introduction to the measurement problems in quantum mechanics and their partial solution by environment-induced decoherence (plus some other important aspects of dcoherence) is given. The point…

Quantum Physics · Physics 2007-05-23 Tulsi Dass

Being the key resource in quantum physics, the proper quantification of coherence is of utmost importance. Amid complex-looking functionals in quantifying coherence, we set forth a simple and easy-to-evaluate approach: Principal diagonal…

Quantum Physics · Physics 2023-02-08 Manis Hazra , Debabrata Goswami

Entropy measures quantify the amount of information and correlation present in a quantum system. In practice, when the quantum state is unknown and only copies thereof are available, one must resort to the estimation of such entropy…

Quantum Physics · Physics 2024-03-27 Ziv Goldfeld , Dhrumil Patel , Sreejith Sreekumar , Mark M. Wilde

We investigate how quantum coherence can be distributed among the several off-diagonal elements of an arbitrary density matrix. An easily computable quantity that captures this variability notion is proposed and it is argued that it…

Quantum Physics · Physics 2026-04-24 Fernando Parisio

While quantum speed-up in solving certain decision problems by a fault-tolerant universal quantum computer has been promised, a timely research interest includes how far one can reduce the resource requirement to demonstrate a provable…

Quantum Physics · Physics 2018-01-01 Jacob Miller , Stephen Sanders , Akimasa Miyake