English
Related papers

Related papers: Parameter Estimation with Reluctant Quantum Walks:…

200 papers

In this article, we study the maximal displacement of critical branching random walk in random environment. Let $M_n$ be the maximal displacement of a particle in generation $n$, and $Z_n$ be the total population in generation $n$, $M$ be…

Probability · Mathematics 2025-03-21 Wenxin Fu , Wenming Hong

We devise a protocol to build 1D time-dependent quantum walks in 1D maximizing the spatial spread throughout the procedure. We allow only one of the physical parameters of the coin-tossing operator to vary, i.e. the angle $\theta$, such…

Quantum Physics · Physics 2020-08-31 Gonzalo Martín-Vázquez , Javier Rodríguez-Laguna

We study the convergence rate of translation-invariant discrete-time quantum dynamics on a one-dimensional lattice. We prove that the cumulative distributions function of the ballistically scaled position $X(n)/{n}$ after $n$ steps…

Mathematical Physics · Physics 2026-01-27 Benjamin Hinrichs , Pascal Mittenbühler

We study the motion of two non-interacting quantum particles performing a random walk on a line and analyze the probability that the two particles are detected at a particular position after a certain number of steps (meeting problem). The…

Quantum Physics · Physics 2007-05-23 M. Stefanak , T. Kiss , I. Jex , B. Mohring

A transition of quantum walk induced by classical randomness changes the probability distribution of the walker from a two-peak structure to a single-peak one when the random parameter exceeds a critical value. We first establish the…

Quantum Physics · Physics 2023-10-02 Christopher Mastandrea , Chih-Chun Chien

Based on studies on four specific networks, we conjecture a general relation between the walk dimensions $d_{w}$ of discrete-time random walks and quantum walks with the (self-inverse) Grover coin. In each case, we find that $d_{w}$ of the…

Statistical Mechanics · Physics 2015-06-03 Stefan Boettcher , Stefan Falkner , Renato Portugal

We investigate quantum walks in multiple dimensions with different quantum coins. We augment the model by assuming that at each step the amplitudes of the coin state are multiplied by random phases. This model enables us to study in detail…

Quantum Physics · Physics 2009-11-13 Jozef Kosik , Vladimir Buzek , Mark Hillery

We study a quantum walker on a one-dimensional lattice with a single defect site characterized by a phase. The spread and localization of discrete-time quantum walks starting at the impurity site are affected by the appearance of bound…

Quantum Physics · Physics 2019-05-10 B. Danacı , G. Karpat , İ. Yalçınkaya , A. L. Subaşı

We consider a random walk in random environment with random holding times, that is, the random walk jumping to one of its nearest neighbors with some transition probability after a random holding time. Both the transition probabilities and…

Probability · Mathematics 2014-12-30 Ryoki Fukushima , Naoki Kubota

The properties of the coinless quantum walk model have not been as thoroughly analyzed as those of the coined model. Both evolve in discrete time steps but the former uses a smaller Hilbert space, which is spanned merely by the site basis.…

Quantum Physics · Physics 2017-09-08 Raqueline A. M. Santos , Renato Portugal , Stefan Boettcher

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 present numerical study of a model of quantum walk in periodic potential on the line. We take the simple view that different potentials affect differently the way the coin state of the walker is changed. For simplicity and definiteness,…

Quantum Physics · Physics 2015-06-16 C. -I. Chou , C. -L. Ho

A connection is made between the random turns model of vicious walkers and random permutations indexed by their increasing subsequences. Consequently the scaled distribution of the maximum displacements in a particular asymmeteric version…

Combinatorics · Mathematics 2007-05-23 P. J. Forrester

Properties of the probability distribution generated by a discrete-time quantum walk, such as the number of peaks it contains, depend strongly on the choice of the initial condition. In the present paper we discuss from this point of view…

Quantum Physics · Physics 2017-01-03 Martin Stefanak , Iva Bezdekova , Igor Jex

We consider a one dimensional sub-ballistic random walk evolving in a parametric i.i.d. random environment. We study the asymptotic properties of the maximum likelihood estimator (MLE) of the parameter based on a single observation of the…

Probability · Mathematics 2014-05-13 Mikael Falconnet , Dasha Loukianova , Arnaud Gloter

We characterize quantumness of the so-called quantum walks (whose dynamics is governed by quantum mechanics) by introducing two computable measures which are stronger than the variance of the walker's position probability distribution. The…

Quantum Physics · Physics 2018-10-09 F. Shahbeigi , S. J. Akhtarshenas , A. T. Rezakhani

We consider a discrete time random walk in one dimension. At each time step the walker jumps by a random distance, independent from step to step, drawn from an arbitrary symmetric density function. We show that the expected positive maximum…

Statistical Mechanics · Physics 2009-11-11 Alain Comtet , Satya N. Majumdar

Quantum walks are well-known for their ballistic dispersion, traveling $\Theta(t)$ away in $t$ steps, which is quadratically faster than a classical random walk's diffusive spreading. In physical implementations of the walk, however, the…

Quantum Physics · Physics 2016-01-25 Thomas G. Wong

We consider homogeneous open quantum random walks on a lattice with finite dimensional local Hilbert space and we study in particular the position process of the quantum trajectories of the walk. We prove that the properly rescaled position…

Probability · Mathematics 2022-06-08 Raffaella Carbone , Federico Girotti , Anderson Melchor Hernandez

We study one-dimensional quantum walk with four internal degrees of freedom resulted from two entangled qubits. We will demonstrate that the entanglement between the qubits and its corresponding coin operator enable one to steer the…

Quantum Physics · Physics 2020-07-01 S. Panahiyan , S. Fritzsche