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Related papers: Quantum backflow effect and nonclassicality

200 papers

Two notions of nonclassicality that have been investigated intensively are: (i) negativity, that is, the need to posit negative values when representing quantum states by quasiprobability distributions such as the Wigner representation, and…

Quantum Physics · Physics 2008-07-07 Robert W. Spekkens

We consider in what sense quantum tunnelling is associated with non-classical probabilistic behaviour. We use the Wigner function quasi-probability description of quantum states. We give a definition of tunnelling that allows us to say…

Quantum Physics · Physics 2021-01-04 Yin Long Lin , Oscar C. O. Dahlsten

It is known that for a non-relativistic quantum particle traveling freely on the $x$-axis, the positional probability can flow in the opposite direction to the particle's velocity. The maximum possible amount of such backflow that can occur…

Quantum Physics · Physics 2016-08-30 A. J. Bracken , J. B. McGuire

Quantum nonlocality is revisited from a novel point of view by studying the problem of an originally classical particle immersed in the stochastic zero-point radiation field (zpf). The entire system is left to evolve until it reaches a…

Quantum Physics · Physics 2011-10-24 L. de la Peña , A. M. Cetto , A. Valdés-Hernández , H. M. França

The probability density of a quantum particle moving freely within a circular ring can exhibit local flow patterns inconsistent with its angular momentum, a phenomenon known as quantum backflow. In this study, we examine a quantum particle…

Quantum Physics · Physics 2024-08-13 Arseni Goussev , Felix Quinque , Jaewoo Joo , Andrew Burbanks

In its original formulation, quantum backflow (QB) is an interference effect that manifests itself as a negative probability transfer for free-particle states comprised of plane waves with only positive momenta. Quantum reentry (QR) is…

Quantum Physics · Physics 2020-08-07 Arseni Goussev

We investigate the nonclassicality of photon-added coherent states in the photon loss channel by exploring the entanglement potential and negative Wigner distribution. The total negative probability defined by the absolute value of the…

Quantum Physics · Physics 2009-11-13 Shang-Bin Li , Xu-Bo Zou , Guang-Can Guo

We analyze two two-mode continuous variable separable states with the same marginal states. We adopt the definition of classicality in the form of well-defined positive Wigner function describing the state and find that although the states…

Quantum Physics · Physics 2016-04-07 Razieh Taghiabadi , Seyed Javad Akhtarshenas , Mohsen Sarbishaei

We show that the quantum wavefunction, interpreted as the probability density of finding a single non-localized quantum particle, which evolves according to classical laws of motion, is an intermediate description of a material quantum…

Quantum Physics · Physics 2007-05-23 Daniela Dragoman

Backflow is a counter-intuitive phenomenon in which a forward propagating quantum particle propagates locally backwards. The actual counter-propagation property associated with this delicate interference phenomenon has not been observed to…

Optics · Physics 2018-11-26 Yaniv Eliezer , Thomas Zacharias , Alon Bahabad

Nonclassicality is a key ingredient for quantum enhanced technologies and experiments involving macro- scopic quantum coherence. Considering various exactly-solvable quantum-oscillator systems, we address the role played by the…

Quantum Physics · Physics 2016-03-23 F. Albarelli , A. Ferraro , M. Paternostro , M. G. A. Paris

The decay of quasi-stable quantum system involves primarily an outgoing probability current density. However, during the transition from exponential to inverse-power-law decay there are time intervals during which this current, although…

Quantum Physics · Physics 2019-11-07 Wytse van Dijk , F. Masafumi Toyama

A measure of nonclassicality of quantum states based on the volume of the negative part of the Wigner function is proposed. We analyze this quantity for Fock states, squeezed displaced Fock states and cat-like states defined as coherent…

Quantum Physics · Physics 2009-11-10 Anatole Kenfack , Karol Zyczkowski

We propose a definition of nonclassicality for a single-mode quantum-optical process based on its action on coherent states. If a quantum process transforms a coherent state to a nonclassical state, it is verified to be nonclassical. To…

The Wigner function of quantum systems is an effective instrument to construct the approximate classical description of the systems for which the classical approximation is possible. During the last time, the Wigner function formalism is…

Quantum Physics · Physics 2009-11-10 Constantin V. Usenko

Viewed as approximations to quantum mechanics, classical evolutions can violate the positive-semidefiniteness of the density matrix. The nature of this violation suggests a classification of dynamical systems based on classical-quantum…

Quantum Physics · Physics 2009-11-06 Salman Habib , Kurt Jacobs , Hideo Mabuchi , Robert Ryne , Kosuke Shizume , Bala Sundaram

A fluid analog of the information flux in the phase-space associated to purity and von Neumann entropy are identified in the Weyl-Wigner formalism of quantum mechanics. Once constrained by symmetry and positiveness, the encountered…

Quantum Physics · Physics 2018-01-17 Alex E. Bernardini , Orfeu Bertolami

Decoherence is a well established process for the emergence of classical mechanics in open quantum systems. However, it can have two different origins or mechanisms depending on the dynamics one is considering, speaking then about intrinsic…

Quantum Physics · Physics 2022-12-14 S. V. Mousavi , S. Miret-Artes

In this paper we discuss relativistic quantum backflow. The general theory of relativistic backflow is written down and it is shown that the backflow can be written as a function of a simple parameter which is defined in terms of…

Quantum Physics · Physics 2020-01-08 Johar M. Ashfaque , J. Lynch , P. Strange

What is fundamentally quantum? We argue that most of the features, problems, and paradoxes -- such as the measurement problem, the Wigner's friend paradox and its proposed solutions, single particle nonlocality, and no-cloning -- allegedly…

Quantum Physics · Physics 2025-04-09 Flavio Del Santo , Nicolas Gisin