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This manuscript gathers and subsumes a long series of works on using QW to simulate transport phenomena. Quantum Walks (QWs) consist of single and isolated quantum systems, evolving in discrete or continuous time steps according to a…

Quantum Physics · Physics 2021-12-23 Giuseppe Di Molfetta

In this study we show a way of achieving the reverse evolution of n-dimensional quantum walks by introducing interventions on the coin degree of freedom during the forward progression of the coin-walker system. Only a single intervention is…

Quantum Physics · Physics 2018-03-23 Mahesh N. Jayakody , Asiri Nanayakkara

We observe that changing a phase at a single point in a discrete quantum walk results in a rather surprising localization effect. For certain values of this phase change the possibility of localization strongly depends on the internal…

The control of quantum walk is made particularly transparent when the initial state is expressed in terms of the eigenstates of the coin operator. We show that the group-velocity density acquires a much simpler form when expressed in this…

Quantum Physics · Physics 2014-05-30 Martin Stefanak , Igor Jex

A discrete-time Quantum Walk (QW) is essentially an operator driving the evolution of a single particle on the lattice, through local unitaries. Some QWs admit a continuum limit, leading to familiar PDEs (e.g. the Dirac equation). Recently…

Quantum Physics · Physics 2016-09-21 Pablo Arrighi , Stefano Facchini

We define a random walk of a particle in $\mathbb{R}^3$ where the space is rotating. The particle is not glued to the space and will collide with it at random times, resulting in changes in its velocity and direction. After many collisions,…

Probability · Mathematics 2023-12-06 Alberto M. Campos , Tarcísio P. R. Campos

We propose a novel implementation of discrete time quantum walks for a neutral atom in an array of optical microtraps or an optical lattice. We analyze a one-dimensional walk in position space, with the coin, the additional qubit degree of…

Quantum Physics · Physics 2009-11-11 K. Eckert , J. Mompart , G. Birkl , M. Lewenstein

Quantum state preparation in high-dimensional systems is an essential requirement for many quantum-technology applications. The engineering of an arbitrary quantum state is, however, typically strongly dependent on the experimental platform…

We show that the standard quantum-walk quantum-to-classical transition, characterized by ballistic-to-diffusive spreading of the walker's position, can be controlled by externally modulating the coin state. We illustrate by showing an…

Quantum Physics · Physics 2013-02-25 Peng Xue , Barry C. Sanders

The "quantum walk" has emerged recently as a paradigmatic process for the dynamic simulation of complex quantum systems, entanglement production and quantum computation. Hitherto, photonic implementations of quantum walks have mainly been…

We revisit the one dimensional discrete time quantum walk with 3 states and the Grover coin. We derive analytic expressions for observed the localization, an long time approximation for the probability density function (PDF). We also…

Quantum Physics · Physics 2014-10-29 Stefan Falkner , Stefan Boettcher

Quantum walks (QWs) describe particles evolving coherently on a lattice. The internal degree of freedom corresponds to a Hilbert space, called coin system. We consider QWs on Cayley graphs of some group $G$. In the literature,…

Discrete-time quantum walks (DTQWs) in random artificial electric and gravitational fields are studied analytically and numerically. The analytical computations are carried by a new method which allows a direct exact analytical…

Quantum Physics · Physics 2017-04-25 G. Di Molfetta , F. Debbasch

The behaviors of one-dimensional quantum random walks are strikingly different from those of classical ones. However, when decoherence is involved, the limiting distributions take on many classical features over time. In this paper, we…

Quantum Physics · Physics 2009-11-13 Kai Zhang

We study a generalized Hadamard walk in one dimension with three inner states. The particle governed by the three-state quantum walk moves, in superposition, both to the left and to the right according to the inner state. In addition to…

Quantum Physics · Physics 2009-11-11 Norio Inui , Norio Konno , Etsuo Segawa

We generalize the quantum random walk protocol for a particle in a one-dimensional chain, by using several types of biased quantum coins, arranged in aperiodic sequences, in a manner that leads to a rich variety of possible wave function…

Quantum Physics · Physics 2009-11-10 Pedro Ribeiro , Perola Milman , Remy Mosseri

Estimation of the coin parameter(s) is an important part of the problem of implementing more robust schemes for quantum simulation using quantum walks. We present the estimation of the quantum coin parameter used for one-dimensional…

Quantum Physics · Physics 2020-07-10 Parth Rajauria , Prateek Chawla , C. M. Chandrashekar

We implement the discrete-time quantum walk model using the continuous-time evolution of the Hamiltonian that includes both the shift and the coin generators. Based on the Trotter-Suzuki first-order approximation, we consider an…

Quantum Physics · Physics 2022-03-03 Jalil Khatibi Moqadam , Marcos Cesar de Oliveira

We address metrological problems where the parameter of interest is encoded in the internal degree of freedom of a discrete-time quantum walker, and provide evidence that coin dimensionality is a potential resource to enhance precision. In…

Quantum Physics · Physics 2025-02-18 Simone Cavazzoni , Luca Razzoli , Giovanni Ragazzi , Paolo Bordone , Matteo G. A. Paris

The conditional shift in the evolution operator of a quantum walk generates entanglement between the coin and position degrees of freedom. This entanglement can be quantified by the von Neumann entropy of the reduced density operator…

Quantum Physics · Physics 2009-11-11 G. Abal , R. Siri , A. Romanelli , R. Donangelo