English
Related papers

Related papers: Negative group delay for Dirac particles traveling…

200 papers

Dirac-electronic tunneling and nonlinear transport properties with both finite and zero energy bandgap are investigated for graphene with a tilted potential barrier under a bias. For validation, results from a finite-difference based…

Mesoscale and Nanoscale Physics · Physics 2020-04-01 Farhana Anwar , Andrii Iurov , Danhong Huang , Godfrey Gumbs , Ashwani Sharma

We investigate specific features in the Wigner time behavior for slow electron elastic scattering by shallow potential wells. We considered two types of potentials wells, the small changes in the parameters of which lead to arising bound…

Quantum Physics · Physics 2019-01-03 M. Ya. Amusia , A. S. Baltenkov

We propose that feedback-delayed manual tracking performance is limited by fundamental constraints imposed by the physics of negative group delay. To test this hypothesis, the results of an experiment in which subjects demonstrate both…

Adaptation and Self-Organizing Systems · Physics 2016-06-27 Henning U. Voss , Nigel Stepp

The Fermi acceleration mechanism is a significant source of cosmic rays. When the width of a potential well changes over time, the velocity of particles within the well also changes. For quantum systems, such dynamics should be described by…

Quantum Physics · Physics 2025-02-21 Qiuyu Shan

In the whole set of solutions of the Dirac equation there is a different class referred to as anomalous. Corresponding anomalous particles are independent of conventional ones. The concept of anomalous particles is applicable to Dirac…

General Physics · Physics 2026-04-10 Boris I. Ivlev

We prove that the classical Dirac equation in the presence of an external (nondynamical) electromagnetic field is a relativistically causal theory. As a corollary, we show that it is impossible to use quantum tunneling to transmit particles…

Quantum Physics · Physics 2023-03-14 Lorenzo Gavassino , Marcelo M. Disconzi

Within the framework of a Dirac bubble potential model for the C60 fullerene shell, we calculated the time delay in slow-electron elastic scattering by C60. It appeared that the time of transmission of an electron wave packet through the…

Atomic and Molecular Clusters · Physics 2018-12-26 M. Ya. Amusia , A. S. Baltenkov

We examine one-dimensional quantum scattering of a Dirac particle off relativistic potential barriers. With proper considerations of Dirac sea, existence of anomalous tunneling at zero incident-energy is revealed for a particular type of…

Quantum Physics · Physics 2009-08-03 Pavel Hejcik , Taksu Cheon

The time delay between the receptions of ultra-relativistic particles emitted simultaneously is a useful observable for both fundamental physics and cosmology. The expression of the delay when the particles travel through an arbitrary…

General Relativity and Quantum Cosmology · Physics 2016-07-19 Pierre Fleury

An expression for the group delay of the FitzHugh-Nagumo model in response to low amplitude input is obtained by linearisation of the cubic term of the voltage equation around its stable fixed-point. It is found that a negative group delay…

Neurons and Cognition · Quantitative Biology 2021-01-05 Akke Mats Houben

A clear consensus on how long it takes a particle to tunnel through a potential barrier has never been so urgently required, since the electron dynamics in strong-field ionization can be resolved on attosecond time-scale in experiment and…

Atomic Physics · Physics 2019-03-19 Xiaolei Hao , Zheng Shu , Weidong Li , Jing Chen

We study the robustness of geometric phase in the presence of parametric noise. For that purpose we consider a simple case study, namely a semiclassical particle which moves adiabatically along a closed loop in a static magnetic field…

Quantum Physics · Physics 2009-05-28 Cosmo Lupo , Paolo Aniello

Recent manifestations of apparently faster-than-light effects confirmed our predictions that the group velocity in transparent optical media can exceed c. Special relativity is not violated by these phenomena. Moreover, in the electronic…

Performance · Computer Science 2015-06-25 Raymond Y. Chiao , Jandir M. Hickmann , Daniel Solli

Gravitational lensing can happen not only for null signal but also timelike signals such as neutrinos and massive gravitational waves in some theories beyond GR. In this work we study the time delay between different relativistic images…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Haotian Liu , Junji Jia

Nonlinear dynamical systems with time delay are abundant in applications, but are notoriously difficult to analyse and predict because delay-induced effects strongly depend on the form of the nonlinearities involved, and on the exact way…

Chaotic Dynamics · Physics 2021-11-03 Natalia B. Janson , Christopher J. Marsden

We generalize here the one-level consideration in our recent paper arXiv:1901.00411 [1] to the case when an electron collides with a potential that have any number of s bound states. We investigate peculiarities in the Wigner time delay…

Atomic Physics · Physics 2019-05-01 M. Ya. Amusia , A. S. Baltenkov

We propose an analytical study of relativistic tunneling through opaque barriers. We obtain a closed formula for the phase time. This formula is in excellent agreement with the numerical simulations and corrects the standard formula…

High Energy Physics - Theory · Physics 2015-05-27 Stefano De Leo , Vinicius Leonardi

We study non-relativistic propagation of Gaussian wave packets in one-dimensional Eckart potential, a barrier, or a well. In the picture used, the transmitted wave packet results from interference between the copies of the freely…

Quantum Physics · Physics 2022-03-10 X. Gutiérrez de la Cal , M. Pons , D. Sokolovski

Group delay for a reflected light pulse from a weakly absorbing dielectric slab is theoretically investigated, and large negative group delay is found for weak absorption near a resonance of the slab ($Re(kd)=m\pi$). The group delays for…

Optics · Physics 2009-11-11 Li-Gang Wang , Shi-Yao Zhu

The Klein paradox is reassessed by considering the properties of a finite square well or barrier in the Dirac equation. It is shown that spontaneous positron emission occurs for a well if the potential is strong enough. The vacuum charge…

Quantum Physics · Physics 2009-10-31 A Calogeracos , N Dombey