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A coinless, discrete-time quantum walk possesses a Hilbert space whose dimension is smaller compared to the widely-studied coined walk. Coined walks require the direct product of the site basis with the coin space, coinless walks operate…

Quantum Physics · Physics 2015-05-27 Renato Portugal , Stefan Boettcher , Stefan Falkner

We set the criteria under which superposition of causal order can be incorporated in to quantum walks. In particular, we show that only periodic quantum walks or those with at least one disorder exhibit Superposition of causal order under…

Quantum Physics · Physics 2025-03-11 Prateek Chawla , Shrikant Utagi , C. M. Chandrashekar

In this paper we present closed-form expressions for the wave function that governs the evolution of the discrete-time quantum walk on a line when the coin operator is arbitrary. The formulas were derived assuming that the walker can either…

Quantum Physics · Physics 2015-02-18 Miquel Montero

Quantum walks have been shown to have a wide range of applications, from artificial intelligence, to photosynthesis, and quantum transport. Quantum stochastic walks (QSWs) generalize this concept to additional non-unitary evolution. In this…

Quantum Physics · Physics 2021-05-26 Peter K. Schuhmacher , Luke C. G. Govia , Bruno G. Taketani , Frank K. Wilhelm

We find out a few ways to improve the realization of entanglement between the internal (spin) and external (position) degrees of freedom of a quantum particle, through the insertion of disordered time steps along a one-dimensional discrete…

Quantum Physics · Physics 2019-11-13 Alexandre C. Orthey , Edgard P. M. Amorim

We design a quantum probing protocol using Quantum Walks to investigate the Quantum Information spreading pattern. We employ Quantum Fisher Information, as a figure of merit, to quantify extractable information about an unknown parameter…

This paper presents a simple model that mimics quantum mechanics (QM) results in terms of probability fields of free particles subject to self-interference, without using Schr\"{o}dinger equation or wavefunctions. Unlike the standard QM…

Quantum Physics · Physics 2015-01-27 Antonio Sciarretta

The effects of quenched disorder on the overdamped motion of a driven particle on a periodic, asymmetric potential is studied. While for the unperturbed potential the transport is due to a regular drift, the quenched disorder induces a…

Soft Condensed Matter · Physics 2009-10-31 M. N. Popescu , C. M. Arizmendi , A. L. Salas-Brito , F. Family

Quantum walks, both discrete (coined) and continuous time, form the basis of several recent quantum algorithms. Here we use numerical simulations to study the properties of discrete, coined quantum walks. We investigate the variation in the…

Quantum Physics · Physics 2008-04-21 Ivens Carneiro , Meng Loo , Xibai Xu , Mathieu Girerd , Viv Kendon , Peter L. Knight

We propose a robust and efficient way to store and transport quantum information via one-dimensional discrete time quantum walks. We show how to attain an effective dispersionless wave packet evolution using only two types of local unitary…

Quantum Physics · Physics 2021-09-30 Rafael Vieira , Gustavo Rigolin , Edgard P. M. Amorim

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 consider random walks in dynamic random environments which arise naturally as spatial embeddings of ancestral lineages in spatial locally regulated population models. In particular, as the main result, we prove the quenched central limit…

Probability · Mathematics 2024-03-15 Matthias Birkner , Andrej Depperschmidt , Timo Schlüter

The interest in quantum walks has been steadily increasing during the last two decades. It is still worth to present new forms of quantum walks that might find practical applications and new physical behaviors. In this work, we define…

Quantum Physics · Physics 2020-04-06 Bruno Chagas , Renato Portugal

Random walks are studied on disordered cellular networks in 2-and 3-dimensional spaces with arbitrary curvature. The coefficients of the evolution equation are calculated in term of the structural properties of the cellular system. The…

Disordered Systems and Neural Networks · Physics 2009-10-28 Tomaso Aste

We analyze a class of continuous time random walks in $\mathbb R^d,d\geq 2,$ with uniformly distributed directions. The steps performed by these processes are distributed according to a generalized Dirichlet law. Given the number of changes…

Probability · Mathematics 2015-06-16 Alessandro De Gregorio

A powerful strategy to accelerate quantum-walk-based search algorithms leverages on resetting protocols, where a detector monitors a target site and the evolution of the walker is restarted if no detection occurs within a fixed time…

Quantum Physics · Physics 2025-11-03 Sayan Roy , Shamik Gupta , Giovanna Morigi

We consider discrete-time nearest-neighbor quantum walks on random environments in one dimension. Using the method based on a path counting, we present both quenched and annealed weak limit theorems for the quantum walk.

Quantum Physics · Physics 2010-05-12 Norio Konno

Based on the Dirac representation of Maxwell equations we present an explicit, discrete space-time, quantum walk-inspired algorithm suitable for simulating the electromagnetic wave propagation and scattering from inhomogeneities within…

We consider discrete-time evolution equations in which the stochastic operator of a classical random walk is replaced by a unitary operator. Such a problem has gained much attention as a framework for coined quantum walks that are essential…

Quantum Physics · Physics 2017-02-27 Stefan Boettcher , Shanshan Li , Renato Portugal

We characterize a close connection between the continuous-time quantum-walk model and a discrete-time quantum-walk version, based on the staggered model with Hamiltonians in a class of Cayley graphs, which can be considered as a…

Quantum Physics · Physics 2018-05-24 Gabriel Coutinho , Renato Portugal
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