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Related papers: Detecting coherence via spectrum estimation

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Incoherent noise is manifest in measurements of expectation values when the underlying ensemble evolves under a classical distribution of unitary processes. While many incoherent processes appear decoherent, there are important differences.…

We propose an alternative framework for quantifying coherence. The framework is based on a natural property of coherence, the additivity of coherence for subspace-independent states, which is described by an operation-independent equality…

Quantum Physics · Physics 2017-01-04 Xiao-Dong Yu , Da-Jian Zhang , G. F. Xu , D. M. Tong

Coherence, being at the heart of interference phenomena, is found to be an useful resource in quantum information theory. Here we want to understand quantum coherence under the combination of two fundamentally dual processes, viz., cloning…

Quantum Physics · Physics 2017-08-15 Sumana Karmakar , Ajoy Sen , Debasis Sarkar

Coherent superposition is a key feature of quantum mechanics that underlies the advantage of quantum technologies over their classical counterparts. Recently, coherence has been recast as a resource theory in an attempt to identify and…

Quantum coherence constitutes a foundational characteristic of quantum mechanics and is integral to emerging quantum resource theories. However, quantum coherence is severely restricted by environmental noise in general quantum processing,…

Quantum Physics · Physics 2024-05-24 Qing-Hua Zhang , Shao-Ming Fei

Basic quantum information measures involved in the information analysis of quantum systems are considered. It is shown that the main quantum information measurement methods depend on whether the corresponding quantum events are compatible…

Quantum Physics · Physics 2007-05-23 B. A. Grishanin , V. N. Zadkov

We establish a rigorous connection between quantum coherence and quantum chaos by employing coherence measures originating from the resource theory framework as a diagnostic tool for quantum chaos. We quantify this connection at two…

Quantum Physics · Physics 2021-06-21 Namit Anand , Georgios Styliaris , Meenu Kumari , Paolo Zanardi

Quantum coherence -- an indispensable resource for quantum technologies -- is known to be distillable from a noisy form using operations that cannot create it. However, distillation exacts a hidden coherent measurement cost, which has not…

Quantum Physics · Physics 2025-04-16 Varun Narasimhachar

The accurate and reliable description of measurement devices is a central problem in both observing uniquely non-classical behaviors and realizing quantum technologies from powerful computing to precision metrology. To date quantum…

Quantum Physics · Physics 2020-01-30 Aonan Zhang , Jie Xie , Huichao Xu , Kaimin Zheng , Han Zhang , Yiu-Tung Poon , Vlatko Vedral , Lijian Zhang

The so-called quantum measurement problems are solved from a new perspective. One of the main observations is that the basic entities of our world are {\it particles}, elementary or composite. It follows that each elementary process, hence…

Quantum Physics · Physics 2023-02-20 Kenichi Konishi

We characterize minimal measurement setups for validating the quantum coherence of an unknown quantum state. We show that for a $d$-level system, the optimal strategy consists of measuring $d$ orthonormal bases such that each measured basis…

Quantum Physics · Physics 2018-06-27 Claudio Carmeli , Teiko Heinosaari , Sabrina Maniscalco , Jussi Schultz , Alessandro Toigo

Decoherence is widely felt to have something to do with the quantum measurement problem, but getting clear on just what is made difficult by the fact that the "measurement problem", as traditionally presented in foundational and…

Quantum Physics · Physics 2015-06-03 David Wallace

The spectrum and coherency are useful quantities for characterizing the temporal correlations and functional relations within and between point processes. This paper begins with a review of these quantities, their interpretation and how…

Biological Physics · Physics 2007-05-23 M. R. Jarvis , P. P. Mitra

Networks based on entangled quantum systems enable interesting applications in quantum information processing and the understanding of the resulting quantum correlations is essential for advancing the technology. We show that the theory of…

Quantum Physics · Physics 2021-05-12 Tristan Kraft , Cornelia Spee , Xiao-Dong Yu , Otfried Gühne

The distribution of coherence in multipartite systems is one of the fundamental problems in the resource theory of coherence. To quantify the coherence in multipartite systems more precisely, we introduce new coherence measures,…

Quantum Physics · Physics 2017-10-25 Kaifeng Bu , Lu Li , Arun Kumar Pati , Shao-Ming Fei , Junde Wu

Purity and coherence of a quantum state are recognized as useful resources for various information processing tasks. In this article, we propose a fidelity based valid measure of purity and coherence monotone and establish a relationship…

Quantum Physics · Physics 2021-04-09 Indrajith V S , R. Muthuganesan , R. Sankaranarayanan

Coherence is a fundamental resource in quantum information processing, which can be certified by a coherence witness. In order to detect all the coherent states, we introduce a useful concept of coherence witness and structure the set of…

Quantum Physics · Physics 2024-10-29 Xue-Na Zhu , Zhi-Xiang Jin , Gui Bao , Shao-Ming Fei

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

Quantum sensing utilize quantum effects, such as entanglement and coherence, to measure physical signals. The performance of a sensing process is characterized by error which requires comparison to a true value. However, in practice, such a…

Quantum Physics · Physics 2024-10-29 Lian-Xiang Cui , Yi-Mu Du , C. P. Sun

A dynamical signature of localization in quantum systems is the absence of transport which is governed by the amount of coherence that configuration space states possess with respect to the Hamiltonian eigenbasis. To make this observation…

Quantum Physics · Physics 2019-12-25 Georgios Styliaris , Namit Anand , Lorenzo Campos Venuti , Paolo Zanardi