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Related papers: Non-classicality of coherent state mixtures

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Quantification of nonclassicality and entanglement in a quantum state is crucial for quantum advantage in information processing and computation. Robustness is one of the tractable measures for quantifying quantum resources. Gaussian states…

Quantum Physics · Physics 2023-09-22 Xiao-yu Chen

Mixed state quantum computation can perform certain tasks which are believed to be efficiently intractable on a classical computer. For a specific model of mixed state quantum computation, namely, {\it deterministic quantum computation with…

Quantum Physics · Physics 2014-12-10 Mazhar Ali

We discuss models of computing that are beyond classical. The primary motivation is to unearth the cause of nonclassical advantages in computation. Completeness results from computational complexity theory lead to the identification of very…

Quantum Physics · Physics 2011-12-22 Animesh Datta , Anil Shaji

Non-classical probability (along with its underlying logic) is a defining feature of quantum mechanics. A formulation that incorporates them, inherently and directly, would promise a unified description of seemingly different prescriptions…

Quantum Physics · Physics 2019-05-21 Soumik Adhikary , Sooryansh Asthana , V. Ravishankar

Although quantum coherence is a basic trait of quantum mechanics, the presence of coherences in the quantum description of a certain phenomenon does not rule out the possibility to give an alternative description of the same phenomenon in…

Quantum Physics · Physics 2018-12-07 Andrea Smirne , Dario Egloff , María García Díaz , Martin B. Plenio , Susana F. Huelga

Quantum discord quantifies non-classical correlations in a quantum system including those not captured by entanglement. Thus, only states with zero discord exhibit strictly classical correlations. We prove that these states are negligible…

Quantum Physics · Physics 2015-05-14 A. Ferraro , L. Aolita , D. Cavalcanti , F. M. Cucchietti , A. Acin

We report investigation on quantum discord in classical second-order interference. In particular, we theoretically show that a bipartite state with D = 0.311 of discord can be generated via classical second-order interference. We also…

In quantum optics, measurement statistics -- for example, photocounting statistics -- are considered nonclassical if they cannot be reproduced with statistical mixtures of classical radiation fields. We have formulated a necessary and…

Quantum Physics · Physics 2024-09-02 V. S. Kovtoniuk , E. V. Stolyarov , O. V. Kliushnichenko , A. A. Semenov

We discuss how to calculate genuine multipartite quantum and classical correlations in symmetric, spatially invariant, mixed $n$-qubit density matrices. We show that the existence of symmetries greatly reduces the amount of free parameters…

Quantum Physics · Physics 2016-10-24 Gian Luca Giorgi , Steve Campbell

Practically applicable criteria for the nonclassicality of quantum states are formulated in terms of different types of moments. For this purpose the moments of the creation and annihilation operators, of two quadratures, and of a…

Quantum Physics · Physics 2009-11-11 E. V. Shchukin , W. Vogel

A path for efficient classical simulation of the DQC1 circuit that estimates the trace of an implementable unitary under the zero discord condition [Phys. Rev. Lett. 105, 190502 (2010)] is presented. This result reinforces the status of…

Quantum Physics · Physics 2025-10-29 Shalin Jose , Akshay Kannan Sairam , Anil Shaji

The convenience of coherent state representation is discussed from the viewpoint of what is in a broad sense called the measurement problem in quantum mechanics. Standard quantum theory in coherent state representation is intrinsically…

Quantum Physics · Physics 2008-02-03 Lajos Diosi

Quantum coherence is a key element in topical research on quantum resource theories and a primary facilitator for design and implementation of quantum technologies. However, the resourcefulness of quantum coherence is severely restricted by…

Quantum Physics · Physics 2015-06-01 Uttam Singh , Manabendra Nath Bera , Himadri Shekhar Dhar , Arun Kumar Pati

Recent measures of nonclassical correlations are motivated by different notions of classicality and operational means. Quantum discord has received a great deal of attention in studies involving quantum computation, metrology, dynamics,…

Quantum Physics · Physics 2014-05-27 Kavan Modi

Contextuality is a key characteristic that separates quantum from classical phenomena and an important tool in understanding the potential advantage of quantum computation. However, when assessing the quantum resources available for quantum…

Quantum Physics · Physics 2026-03-04 Maiyuren Srikumar , Stephen D. Bartlett , Angela Karanjai

Although the foundations of quantum and classical physics are much different, it is often difficult to pinpoint which features of a particular system are intrinsically "quantum". Perhapse, the most clear-cut distinction between "classical"…

Quantum Physics · Physics 2015-02-05 Piotr Szańkowski

Multipartite quantum systems show properties which do not admit a classical explanation. In particular, even nonentangled states can enjoy a kind of quantum correlations called quantum discord. I discuss some recent results on the role of…

Quantum Physics · Physics 2015-11-04 Davide Girolami

The threshold between classical and nonclassical two-qubit states is drawn at the place when these states can no longer be described by classical correlations, i.e., quantum discord or entanglement appear. However, to check if the…

Quantum Physics · Physics 2013-06-05 Karol Bartkiewicz , Karel Lemr , Antonín Černoch , Jan Soubusta

The pair coherent states for a two-mode radiation field are known to belong to a family of states with non-Gaussian wave function. The nature of quantum entanglement between the two modes and some features of non-classicality are studied…

Quantum Physics · Physics 2016-08-08 G. S. Agarwal , Asoka Biswas

Quantum coherence and non-classical correlation are key features of quantum world. Quantifying coherence and non-classical correlation are two key tasks in quantum information theory. First, we present a bona fide measure of quantum…

Quantum Physics · Physics 2018-06-29 Zhi-Xiang Jin , Shao-Ming Fei