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Related papers: Fluctuations of Quantum Random Walks on Circles

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A random walk is known as a random process which describes a path including a succession of random steps in the mathematical space. It has increasingly been popular in various disciplines such as mathematics and computer science.…

Social and Information Networks · Computer Science 2020-08-11 Feng Xia , Jiaying Liu , Hansong Nie , Yonghao Fu , Liangtian Wan , Xiangjie Kong

Recently, several groups have investigated quantum analogues of random walk algorithms, both on a line and on a circle. It has been found that the quantum versions have markedly different features to the classical versions. Namely, the…

Quantum Physics · Physics 2009-11-07 B. C. Travaglione , G. J. Milburn

The classicalization of a decoherent discrete-time quantum walk on a line or an n-cycle can be demonstrated in various ways that do not necessarily provide a geometry-independent description. For example, the position probability…

Quantum Physics · Physics 2010-06-25 R. Srikanth , Subhashish Banerjee , C. M. Chandrashekar

We consider a one-dimensional space-inhomogeneous discrete time quantum walk. This model is the Hadamard walk with one defect at the origin which is different from the model introduced by Wojcik et al. [14]. We obtain a stationary measure…

Mathematical Physics · Physics 2015-07-31 Takako Endo , Norio Konno , Etsuo Segawa , Masato Takei

The evolution of a walker in standard "Discrete-time Quantum Walk (DTQW)" is determined by coin and shift unitary operators. The conditional shift operator shifts the position of the walker to right or left by unit step size while the…

Quantum Physics · Physics 2020-03-03 Rashid Ahmad , Safia Bibi , Uzma Sajjad

Quantum walks are standard tools for searching graphs for marked vertices, and they often yield quadratic speedups over a classical random walk's hitting time. In some exceptional cases, however, the system only evolves by sign flips,…

Quantum Physics · Physics 2017-05-05 Thomas G. Wong , Raqueline A. M. Santos

Quantum and random walks have been shown to be equivalent in the following sense: a time-dependent random walk can be constructed such that its vertex distribution at all time instants is identical to the vertex distribution of any…

Quantum Physics · Physics 2023-06-13 Matheus G. Andrade , Franklin de Lima Marquezino , Daniel R. Figueiredo

Quantum walks are expected to provide useful algorithmic tools for quantum computation. This paper introduces absorbing probability and time of quantum walks and gives both numerical simulation results and theoretical analyses on Hadamard…

Quantum Physics · Physics 2009-11-07 Tomohiro Yamasaki , Hirotada Kobayashi , Hiroshi Imai

We consider quantum random walks on congested lattices and contrast them to classical random walks. Congestion is modelled with lattices that contain static defects which reverse the walker's direction. We implement a dephasing process…

Quantum Physics · Physics 2016-04-28 Keith R. Motes , Alexei Gilchrist , Peter P. Rohde

The role of classical noise in quantum walks (QW) on integers is investigated in the form of discrete dichotomic random variable affecting its reshuffling matrix parametrized as a SU2)/U(1) coset element. Analysis in terms of quantum…

Quantum Physics · Physics 2015-06-05 D. Ellinas , A. J. Bracken , I. Smyrnakis

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

Quantum random walks are the quantum counterpart of classical random walks, and were recently studied in the context of quantum computation. A quantum random walker is subject to self interference, leading to a remarkably different behavior…

It has been discovered that open quantum walks diffusively distribute in space, since they were introduced in 2012. Indeed, some limit distributions have been demonstrated and most of them are described by Gaussian distributions. We operate…

Quantum Physics · Physics 2021-12-20 Takuya Machida

The mean squared displacement has been widely used as the primary metric for comparing quantum and classical random walks, with quantum walks showing quadratic scaling versus linear scaling for classical walks. However, this comparison may…

Quantum Physics · Physics 2026-03-20 Jan Wójcik

Classical random walks and Markov processes are easily described by Hopf algebras. It is also known that groups and Hopf algebras (quantum groups) lead to classical and quantum diffusions. We study here the more primitive notion of a…

High Energy Physics - Theory · Physics 2015-06-26 S. Majid

Quantum walks are counterparts of classical random walks. They spread faster, which can be exploited in information processing tasks, and constitute a versatile simulation platform for many quantum systems. Yet, some of their properties can…

Quantum Physics · Physics 2021-08-04 Xiaoxiao Chen , Zhe Meng , Jian Li , Jiazhi Yang , Anning Zhang , Tomasz Kopyciuk , Pawel Kurzynski

The two major discrete time formulations for quantum walks, coined and scattering, are unitarily equivalent for arbitrary position dependent transition amplitudes and any topology (PRA {\bf 80}, 052301 (2009)). Although the proof explicit…

Quantum Physics · Physics 2013-04-15 B F Venancio , F M Andrade , M G E da Luz

We show how a quantum walk can be implemented for the first time in a quantum quincunx created via superconducting circuit quantum electrodynamics (QED), and how interpolation from quantum to random walk is implemented by controllable…

Quantum Physics · Physics 2008-10-29 Peng Xue , Barry C. Sanders , Alexandre Blais , Kevin Lalumiere

Quantum walks are quantum counterparts of random walks and their probability distributions are different from each other. A quantum walker distributes on a Hilbert space and it is observed at a location with a probability. The finding…

Quantum Physics · Physics 2025-08-26 Takuya Machida

Quantum walks have emerged as an interesting approach to quantum information processing, exhibiting many unique properties compared to the analogous classical random walk. Here we introduce a model for a discrete-time quantum walk with…

Quantum Physics · Physics 2013-05-08 Peter P. Rohde , Gavin K. Brennen , Alexei Gilchrist