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Related papers: Quantum backflow effect and nonclassicality

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We analyse the quantum backflow effect and extend it, as a limiting constraint to its spatial extent, for scattering situations in the presence of a purely transmitting discontinuous jump-defect. Analytical and numerical comparisons are…

Quantum Physics · Physics 2020-10-07 Alexandre Hefren de Vasconcelos

The presence of negative values in the Wigner quasiprobability distribution is deemed one of the hallmarks of nonclassical phenomena in quantum systems. Here we demonstrate a classical model of squeezed light that, when combined with…

Quantum Physics · Physics 2026-01-27 Brian R. La Cour

$P$-divisibility is a central concept in both classical and quantum non-Markovian processes; in particular, it is strictly related to the notion of information backflow. When restricted to a fixed commutative algebra generated by a complete…

Quantum Physics · Physics 2024-11-27 Fabio Benatti , Dariusz Chruściński , Giovanni Nichele

Phase-space features of the Wigner flow for an anharmonic quantum system driven by the harmonic oscillator potential modified by the addition of an inverse square (one-dimension Coulomb-like) contribution are analytically described in terms…

Quantum Physics · Physics 2018-12-05 Alex E. Bernardini

Quantum Back Flow (QBF), discovered quite a few years back, is a generic purely quantum phenomenon, in which the probability of finding a particle in a direction is non-zero (and increasing for a certain period of time) even when the…

High Energy Physics - Theory · Physics 2021-12-08 Dripto Biswas , Subir Ghosh

Quantum backflow is a surprising phenomenon in which a quantum particle, moving in one dimension and with a state of rightwards momentum, can exhibit a net probability transfer to the left-hand half-line over a finite time interval. We…

Quantum Physics · Physics 2025-11-13 Christopher J. Fewster , Harkan J. Kirk-Karakaya

States with a negative Wigner function, a significant subclass of nonclassical states, serve as a valuable resource for various quantum information processing tasks. Here, we provide a criterion for detecting such quantum states…

Quantum Physics · Physics 2025-03-06 Bivas Mallick , Sudip Chakrabarty , Saheli Mukherjee , Ananda G. Maity , A. S. Majumdar

Transition from quantum to semiclassical behaviour and loss of quantum coherence for inhomogeneous perturbations generated from a non-vacuum initial state in the early Universe is considered in the Heisenberg and the Schr\"odinger…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Julien Lesgourgues , David Polarski , Alexei A. Starobinsky

Quantum mechanics introduces the possibility for particles to move in a direction opposite to their momentum -- a counter-intuitive and classically impossible phenomenon known as quantum backflow. The magnitude of this effect is relatively…

Quantum Physics · Physics 2025-03-13 Maximilien Barbier , Arseni Goussev

We show that classicality emerges during quantum phase transitions due to parametric interactions without coupling to environments. The Wigner functions are explicitly calculated for the Gaussian vacuum, number, and thermal states of a free…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sang Pyo Kim , Chul H. Lee

The left-to-right motion of a free quantum Gaussian wave packet can be accompanied by the right-to-left flow of the probability density, the effect recently studied by Villanueva [Am. J. Phys. 88, 325 (2020)]. Using the Wigner…

Quantum Physics · Physics 2020-10-27 Arseni Goussev

In classical mechanics the local exponential instability effaces the memory of initial conditions and leads to practical irreversibility. In striking contrast, quantum mechanics appears to exhibit strong memory of the initial state. We…

Chaotic Dynamics · Physics 2008-10-07 Valentin V. Sokolov , Oleg V. Zhirov

We demonstrate that the Wigner function of a pure quantum state is a wave function in a specially tuned Dirac bra-ket formalism and argue that the Wigner function is in fact a probability amplitude for the quantum particle to be at a…

Quantum Physics · Physics 2013-11-20 Denys I. Bondar , Renan Cabrera , Dmitry V. Zhdanov , Herschel A. Rabitz

We successively pass two $V$-type three-level atoms through a single-mode cavity field. Considering the field to be initially in a classical state, we evaluate various statistical properties such as the quasiprobability $Q$ function, Wigner…

Quantum Physics · Physics 2023-04-13 Arpita Chatterjee

Gravity gradient is known as a serious systematic effect in atomic tests of the universality of free fall, where the initial central position and velocity of atoms need to be exactly controlled. In this paper, we study quantum free fall…

Quantum Physics · Physics 2020-01-15 M. Zhang , Y. Wang

The transition from classical to quantum behavior for chaotic systems is understood to be accompanied by the suppression of chaotic effects as the relative size of $\hbar$ is increased. We show evidence to the contrary in the behavior of…

Quantum Physics · Physics 2009-11-13 Arie Kapulkin , Arjendu K. Pattanayak

We propose a Wigner function based parameter that can be used as an indicator of quantum chaos. This parameter is defined as "entropy" from the time-dependence of "non-classicallity" proposed in \cite{KZ04}. We perform our considerations…

Quantum Physics · Physics 2012-04-02 A. Kowalewska-Kudłaszyk , J. K. Kalaga , W. Leoński

In the arrival time problem in quantum mechanics, a standard formula that frequently emerges as the probability for crossing the origin during a given time interval is the current integrated over that time interval. This is semiclassically…

Quantum Physics · Physics 2015-05-13 J. J. Halliwell , J. M. Yearsley

Weak values are average quantities,therefore investigating their associated variance is crucial in understanding their place in quantum mechanics. We develop the concept of a position-postselected weak variance of momentum as cohesively as…

Quantum Physics · Physics 2015-08-10 M. R. Feyereisen

Quantum particles and classical particles are described in a common setting of classical statistical physics. The property of a particle being "classical" or "quantum" ceases to be a basic conceptual difference. The dynamics differs,…

Quantum Physics · Physics 2015-05-13 C. Wetterich