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Related papers: Quantum coherence in the presence of unobservable …

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Recently, the basic concept of quantum coherence (or superposition) has gained a lot of renewed attention, after Baumgratz et al. [PRL 113:140401 (2014)], following \AA{}berg [arXiv:quant-ph/0612146], have proposed a resource theoretic…

Quantum Physics · Physics 2017-08-01 Tanmoy Biswas , María García Díaz , Andreas Winter

In the past decades, quantum entanglement has been recognized to be the basic resource in quantum information theory. A fundamental need is then the understanding its qualification and its quantification: Is the quantum state entangled, and…

Quantum Physics · Physics 2013-02-20 Szilárd Szalay

Quantifying quantum coherence is a key task in the resource theory of coherence. Here we establish a good coherence monotone in terms of a state conversion process, which automatically endows the coherence monotone with an operational…

Quantum Physics · Physics 2020-07-01 Deng-hui Yu , Li-qiang Zhang , Chang-shui Yu

Coherence of a quantum state intrinsically depends on the choice of the reference basis. A natural question to ask is the following: if we use two or more incompatible reference bases, can~there be some trade-off relation between the…

Quantum Physics · Physics 2016-07-20 Uttam Singh , Arun Kumar Pati , Manabendra Nath Bera

The peculiar uncertainty or randomness of quantum measurements stems from coherence, whose information-theoretic characterization is currently under investigation. Under the resource theory of coherence, it is interesting to investigate…

Quantum Physics · Physics 2019-10-25 Xiao Yuan , Qi Zhao , Davide Girolami , Xiongfeng Ma

Quantum coherence is one of the primary non-classical features of quantum systems. While protocols such as the Leggett-Garg inequality (LGI) and quantum tomography can be used to test for the existence of quantum coherence and dynamics in a…

Quantum Physics · Physics 2012-12-04 Che-Ming Li , Neill Lambert , Yueh-Nan Chen , Guang-Yin Chen , Franco Nori

It is shown that quantum mechanics is noncontextual if quantum properties are represented by subspaces of the quantum Hilbert space (as proposed by von Neumann) rather than by hidden variables. In particular, a measurement using an…

Quantum Physics · Physics 2013-02-21 Robert B. Griffiths

We present a general way of quantifying the entropic uncertainty of quantum field configurations in phase space in terms of entropic distinguishability with respect to the vacuum. Our approach is based on the functional Husimi…

Quantum Physics · Physics 2024-07-24 Sara Ditsch , Tobias Haas

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

The uncertainty principle imposes a fundamental limit on predicting the measurement outcomes of incompatible observables even if complete classical information of the system state is known. The situation is different if one can build a…

Quantum Physics · Physics 2021-07-21 Huangjun Zhu

A generic model of measurement device which is able to directly measure commonly used quantum-state characteristics such as fidelity, overlap, purity and Hilbert-Schmidt distance for two general uncorrelated mixed states is proposed. In…

Quantum Physics · Physics 2009-11-07 Radim Filip

Quantum coherence as the fundamental characteristic of quantum physics, provides the valuable resource for quantum computation in exceeding the power of classical algorithms. The exploration of quantum coherence in relativistic systems is…

Quantum Physics · Physics 2016-01-13 Xu Chen , Chunfeng Wu , Hong-Yi Su , Chang-Liang Ren , Jing-Ling Chen

The concept of quantum coherence, including various ways to quantify the degree of coherence with respect to the prescribed basis, is currently the subject of active research. The complementarity of quantum coherence in different bases was…

Quantum Physics · Physics 2017-09-08 Alexey E. Rastegin

Short pulses from mode-locked lasers can produce background-free atomic fluorescence by allowing temporal separation of the prompt incidental scatter from the subsequent atomic emission. We use this to improve quantum state detection of…

Atomic Physics · Physics 2020-08-26 Conrad Roman , Anthony Ransford , Michael Ip , Wesley C. Campbell

We analyze the light scattered by a single InAs quantum dot interacting with a resonant continuous-wave laser. High resolution spectra reveal clear distinctions between coherent and incoherent scattering, with the laser intensity spanning…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 K. Konthasinghe , J. Walker , M. Peiris , C. K. Shih , Y. Yu , M. F. Li , J. F. He , L. J. Wang , H. Q. Ni , Z. C. Niu , A. Muller

Recent advances in laser interactions with coherent free electrons have enabled to shape the electron's quantum state. Each electron becomes a superposition of energy levels on an infinite quantized ladder, shown to contain up to thousands…

Quantum Physics · Physics 2023-01-04 Guy Braiman , Ori Reinhardt , Chen Mechel , Omer Levi , Ido Kaminer

Given a preferred orthonormal basis $B$ in the Hilbert space of a quantum system we define a measure of the coherence generating power of a unitary operation with respect to $B$. This measure is the average coherence generated by the…

Quantum Physics · Physics 2017-05-10 Paolo Zanardi , Georgios Styliaris , Lorenzo Campos Venuti

The concept of physical twin observables (PTO) for bipartite quantum states,introduced and proved relevant for quantum information theory in recent work, is substantially simplified. The relation of observable and state is studied in detail…

Quantum Physics · Physics 2009-11-10 Fedor Herbut

A unified conceptual foundation of classical and quantum physics is given, free of undefined terms. Ensembles are defined by extending the `probability via expectation' approach of Whittle to noncommuting quantities. This approach carries…

Quantum Physics · Physics 2007-05-23 Arnold Neumaier

The coherent superposition of states, in combination with the quantization of observables, represents one of the most fundamental features that mark the departure of quantum mechanics from the classical realm. Quantum coherence in many-body…

Quantum Physics · Physics 2017-11-01 Alexander Streltsov , Gerardo Adesso , Martin B. Plenio