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Related papers: Free Dirac evolution as a quantum random walk

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We investigate the properties of a quantum walk which can simulate the behavior of a spin $1/2$ particle in a model with an ordinary spatial dimension, and one extra dimension with warped geometry between two branes. Such a setup…

Quantum Physics · Physics 2022-09-19 Andreu Anglés-Castillo , Armando Pérez

Dirac particle represents a fundamental constituent of our nature. Simulation of Dirac particle dynamics by a controllable quantum system using quantum walks will allow us to investigate the non-classical nature of dynamics in its discrete…

Quantum Physics · Physics 2019-02-05 Arindam Mallick , Sanjoy Mandal , Anirban Karan , C. M. Chandrashekar

It is shown that, in Dirac theory, there is a spatial velocity of a free electron which commutes with the Hamiltonian, so it is a conserved quantity of the motion. Furthermore, there is a spatial orbital angular momentum which also commutes…

General Physics · Physics 2007-05-23 Lu Lin

Localization of relativistic particles have been of great research interests over many decades. We investigate the time evolution of the Gaussian wave packets governed by the one dimensional Dirac equation. For the free Dirac equation, we…

Quantum Physics · Physics 2016-05-09 Atis Yosprakob , Sujin Suwanna

The phenomenon of localization usually happens due to the existence of disorder in a medium. Nevertheless, certain quantum systems allow dynamical localization solely due to the nature of internal interactions. We study a discrete time…

Quantum Physics · Physics 2021-02-24 B. Danacı , İ. Yalçınkaya , B. Çakmak , G. Karpat , S. P. Kelly , A. L. Subaşı

This paper is an investigation of the class of real classical Markov processes without a birth process that will generate the Dirac equation in 1+1 dimensions. The Markov process is assumed to evolve in an extra (ordinal) time dimension.…

Quantum Physics · Physics 2007-05-23 M. Ibison

The quantum walk is a quantum counterpart of the classical random walk that exhibits nonclassical behaviors and outperforms the classical random walk in various aspects. It has been known that a single particle can be propagated by a…

Quantum Physics · Physics 2024-12-09 Daer Feng , Shengshi Pang

We consider the asymptotic evolution of a relativistic spin-1/2-particle. i.e. a particle whose wavefunction satisfies the Dirac equation with external static potential. We prove that the probability for the particle crossing a (detector)…

Mathematical Physics · Physics 2009-11-07 D. Duerr , P. Pickl

We investigate the relation between transport properties and entanglement between the internal (spin) and external (position) degrees of freedom in one-dimensional discrete time quantum walks. We obtain closed-form expressions for the…

Quantum Physics · Physics 2020-04-08 Alexandre C. Orthey , Edgard P. M. Amorim

We address the propagation of the spin along classical trajectories for a 1/2-spin particle obeying the Dirac equation with scalar potentials. Focusing on classical trajectories as the exact propagation of wave-function discontinuities we…

Quantum Physics · Physics 2014-12-24 Jesús Rubio , Alfredo Luis

The phenomenon of spin-dependent quantum scattering in two-dimensional (2D) pseudospin-1/2 Dirac materials leading to a relativistic quantum chimera was recently uncovered. We investigate spin-dependent Dirac electron optics in 2D…

Mesoscale and Nanoscale Physics · Physics 2024-08-23 Li-Li Ye , Chen-Di Han , Ying-Cheng Lai

A quantum walk describes the discrete unitary evolution of a quantum particle on a discrete graph. Some quantum walks, referred to as the Weyl and Dirac quantum walks, provide a description of the free evolution of relativistic quantum…

Quantum Physics · Physics 2020-09-08 Luca Apadula , Alessandro Bisio , Giacomo Mauro D'Ariano , Paolo Perinotti

We show that the coined quantum walk on a line can be understood as an interference phenomenon, can be classically implemented, and indeed already has been. The walk is essentially two independent walks associated with the different coin…

Quantum Physics · Physics 2009-11-10 Peter L. Knight , Eugenio Roldan , J. E. Sipe

In this paper we focus our attention on a particle that follows a unidirectional quantum walk, an alternative version of the nowadays widespread discrete-time quantum walk on a line. Here the walker at each time step can either remain in…

Quantum Physics · Physics 2013-08-01 Miquel Montero

Quantum walks behave differently from what we expect and their probability distributions have unique structures. They have localization, singularities, a gap, and so on. Those features have been discovered from the view point of mathematics…

Quantum Physics · Physics 2016-04-05 Takuya Machida

Discrete-time Quantum Walks (QWs) are transportation models of single quantum particles over a lattice. Their evolution is driven through causal and local unitary operators. QWs are a powerful tool for quantum simulation of fundamental…

We introduce the concept of a quantum walk with two particles and study it for the case of a discrete time walk on a line. A quantum walk with more than one particle may contain entanglement, thus offering a resource unavailable in the…

Quantum Physics · Physics 2007-05-23 Y. Omar , N. Paunkovic , L. Sheridan , S. Bose

A causally well-behaved solution of the localization problem for the free electron is given, with natural space-time transformation properties, in terms of Dirac's position operator. It is shown that, although this operator does not…

Quantum Physics · Physics 2008-11-26 A. J. Bracken , G. F. Melloy

Coined quantum walks may be interpreted as the motion in position space of a quantum particle with a spin degree of freedom; the dynamics are determined by iterating a unitary transformation which is the product of a spin transformation and…

Quantum Physics · Physics 2007-05-23 Alex D. Gottlieb , Svante Janson , Petra F. Scudo

We analyze in detail the discrete--time quantum walk on the line by separating the quantum evolution equation into Markovian and interference terms. As a result of this separation, it is possible to show analytically that the quadratic…

Quantum Physics · Physics 2009-11-10 A. Romanelli , A. C. Sicardi-Schifino , R. Siri , G. Abal , A. Auyuanet , R. Donangelo