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The study of quantum walk processes has been widely divided into two standard variants, the discrete-time quantum walk (DTQW) and the continuous-time quantum walk (CTQW). The connection between the two variants has been established by…

Quantum Physics · Physics 2008-11-08 C. M. Chandrashekar

We present a mathematical formalism for the description of unrestricted quantum walks with entangled coins and one walker. The numerical behaviour of such walks is examined when using a Bell state as the initial coin state, two different…

Quantum Physics · Physics 2009-11-10 S. E. Venegas-Andraca , J. L. Ball , K. Burnett , S. Bose

A scheme for implementing the discrete-time quantum walk on the Bloch sphere is proposed, which is closely related to the SU(2) group. A spin cluster serves as the walker, whereas its location on the Bloch sphere is described by the spin…

Quantum Physics · Physics 2022-04-25 Liwei Duan

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

The most elementary quantum walk is characterized by a 2-dimensional unitary coin flip matrix, which can be parameterized by 4 real variables. The influence of the choice of the coin flip matrix on the time evolution operator is analysed in…

Quantum Physics · Physics 2015-01-30 Lauri Lehman

We present a new scheme for a discrete-time quantum walk on two- and three-dimensional lattices using a two-state particle. We use different Pauli basis as translational eigestates for different axis and show that the coin operation, which…

Quantum Physics · Physics 2015-03-19 C. M. Chandrashekar

We investigate the ballistic spreading behavior of the one-dimensional discrete time quantum walks whose time evolution is driven by any balanced quantum coin. We obtain closed-form expressions for the long-time variance of position of…

Quantum Physics · Physics 2017-12-07 Alexandre C. Orthey , Edgard P. M. Amorim

Discrete-time quantum walk (DTQW) represents a convenient mathematical framework for describing the motion of a particle on a discrete set of positions when this motion is conditioned by the values of certain internal degrees of freedom,…

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

We look at two possible routes to classical behavior for the discrete quantum random walk on the line: decoherence in the quantum ``coin'' which drives the walk, or the use of higher-dimensional coins to dilute the effects of interference.…

Quantum Physics · Physics 2009-11-07 Todd A. Brun , Hilary A. Carteret , Andris Ambainis

Quantum walks, both discrete and continuous, serve as fundamental tools in quantum information processing with diverse applications. This work introduces a hybrid quantum walk model that integrates the coin mechanism of discrete walks with…

Quantum Physics · Physics 2025-09-12 Tianen Chen , Yun Shang

In this work the quantum random walk search algorithm with walk coin constructed by generalized Householder reflection and phase multiplier has been studied. The coin register is one qudit with arbitrary dimension. Monte Carlo simulations,…

Quantum Physics · Physics 2021-12-06 Hristo Tonchev , Petar Danev

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

Hitting times for discrete quantum walks on graphs give an average time before the walk reaches an ending condition. To be analogous to the hitting time for a classical walk, the quantum hitting time must involve repeated measurements as…

Quantum Physics · Physics 2009-11-11 Hari Krovi , Todd A. Brun

The aim of this paper is to build quantum circuits that implement discrete-time quantum walks having an arbitrary position-dependent coin operator. The position of the walker is encoded in base 2: with $n$ wires, each corresponding to one…

Quantum walks, both discrete (coined) and continuous time, form the basis of several quantum algorithms and have been used to model processes such as transport in spin chains and quantum chemistry. The enhanced spreading and mixing…

Quantum Physics · Physics 2010-12-10 Godfrey Leung , Paul Knott , Joe Bailey , Viv Kendon

We propose an implementation of a quantum walk on a circle on an optomechanical system by encoding the walker on the phase space of a radiation field and the coin on a two-level state of a mechanical resonator. The dynamics of the system is…

Quantum Physics · Physics 2015-09-24 Jalil Khatibi Moqadam , Renato Portugal , Marcos Cesar de Oliveira

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

A distinctive feature of non-Hermitian systems is the skin effect, which has attracted widespread attention in recent studies. Quantum walks provide a powerful platform for exploring the underlying mechanisms of the non-Hermitian skin…

Quantum Physics · Physics 2025-08-25 Ding Cheng , Yi Li , Hao Zhao , Haijun Kang , Cui Kong , Jiguo Wang , Feng Mei , Chuanjia Shan , Jibing Liu

We discuss the model of a one-dimensional, discrete-time walk on a line with spatial heterogeneity in the form of a variable set of ultrametric barriers. Inspired by the homogeneous quantum walk on a line, we develop a formalism by which…

Quantum Physics · Physics 2020-07-08 Stefan Boettcher

Although quantum walks exhibit peculiar properties that distinguish them from random walks, classical behavior can be recovered in the asymptotic limit by destroying the coherence of the pure state associated to the quantum system. Here I…

Quantum Physics · Physics 2016-06-16 Miquel Montero