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A quantum walk on a toral phase space involving translations in position and its conjugate momentum is studied in the simple context of a coined walker in discrete time. The resultant walk, with a family of coins parametrized by an angle is…

Quantum Physics · Physics 2018-09-26 Sivaprasad Omanakuttan , Arul Lakshminarayan

We show that quantum walks interpolate between a coherent `wave walk' and a random walk depending on how strongly the walker's coin state is measured; i.e., the quantum walk exhibits the quintessentially quantum property of complementarity,…

Quantum Physics · Physics 2009-11-10 Viv Kendon , Barry C. Sanders

Discrete-time quantum walk evolve by a unitary operator which involves two operators a conditional shift in position space and a coin operator. This operator entangles the coin and position degrees of freedom of the walker. In this paper,…

Quantum Physics · Physics 2012-07-10 S. Salimi , R. Yosefjani

The quantum walk is a dynamical protocol which describes the motion of spinful particles on a lattice. Also, it has been demonstrated to be a powerful platform to explore topological quantum matter. Recently, the quantum walk in coherent…

Quantum Physics · Physics 2018-09-19 Zi-Yong Ge , Heng Fan

We investigate the evolution dynamics of inhomogeneous discrete-time one-dimensional quantum walks displaying long-range correlations in both space and time. The associated quantum coin operators are built to exhibit a random inhomogeneity…

Quantum Physics · Physics 2023-07-12 A. R. C. Buarque , F. S. Passos , W. S. Dias , E. P. Raposo

We explore the notion of generated entropy in open quantum systems. We focus on the study of the discrete-time quantum walk on the line, from the entropy production perspective. We argue that the evolution of the coin can be modeled as an…

Quantum Physics · Physics 2020-04-13 Andrés Vallejo , Alejandro Romanelli , Raúl Donangelo , Renato Portugal

The staggered quantum walk is a type of discrete-time quantum walk model without a coin which can be generated on a graph using particular partitions of the graph nodes. We design Hamiltonians for potential realization of the staggered…

Quantum Physics · Physics 2018-07-25 Jalil Khatibi Moqadam , Ali T. Rezakhani

One of the unique features of discrete-time quantum walks is called trapping, meaning the inability of the quantum walker to completely escape from its initial position, albeit the system is translationally invariant. The effect is…

Quantum Physics · Physics 2020-07-15 Bálint Kollár , András Gilyén , Iva Tkáčová , Tamás Kiss , Igor Jex , Martin Štefaňák

Discrete-time quantum walks are considered a counterpart of random walks and the study for them has been getting attention since around 2000. In this paper, we focus on a quantum walk which generates a probability distribution splitting to…

Quantum Physics · Physics 2018-05-08 Takuya Machida

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

Quantum random walks, - coined, lattice ones, - exhibit ballistic behavior with fascinating asymptotic patterns of the amplitudes. We show that averaging over the coins (using the Haar measure), these patterns blend into a spline. Also, we…

Mathematical Physics · Physics 2021-08-11 Yuliy Baryshnikov

Interplay between quantum interference and classical randomness can enhance performance of various quantum information tasks. In the present paper we analyze recurrence phenomena in the discrete-time quantum stochastic walk on a line, which…

Quantum Physics · Physics 2026-01-28 Martin Stefanak , Vaclav Potocek , Iskender Yalcinkaya , Aurel Gabris , Igor Jex

While completely self-avoiding quantum walks have the distinct property of leading to a trivial unidirectional transport of a quantum state, an interesting and non-trivial dynamics can be constructed by restricting the self-avoidance to a…

Quantum Physics · Physics 2015-12-22 Takuya Machida , C. M. Chandrashekar , Norio Konno , Thomas Busch

Discrete-time quantum walk in one-dimension is studied from a path-integral perspective. This enables derivation of a closed-form expression for amplitudes corresponding to any coin-position basis of the state vector of the quantum walker…

Quantum Physics · Physics 2018-03-02 Karthik S. Joshi , S. K. Srivatsa , R. Srikanth

This paper examines the stability of the quantum random walk search algorithm, when the walk coin is constructed by generalized Householder reflection and additional phase shift, against inaccuracies in the phases used to construct the…

Quantum Physics · Physics 2021-07-06 Hristo Tonchev , Petar Danev

The evolution operator of a discrete-time quantum walk involves a conditional shift in position space which entangles the coin and position degrees of freedom of the walker. After several steps, the coin-position entanglement (CPE)…

Quantum Physics · Physics 2015-05-13 Mostafa Annabestani , Mohammad Reza Abolhasani , Gonzalo Abal

We perform the scattering analysis of the evolution operator of quantum walks with an anisotropic coin, and we prove a weak limit theorem for their asymptotic velocity. The quantum walks that we consider include one-defect models, two-phase…

Mathematical Physics · Physics 2018-06-13 S. Richard , A. Suzuki , R. Tiedra de Aldecoa

The entanglement between the position and coin state of a $N$-dimensional quantum walker is shown to lead to a thermodynamic theory. The entropy, in this thermodynamics, is associated to the reduced density operator for the evolution of…

Quantum Physics · Physics 2015-06-22 Alejandro Romanelli , Raul Donangelo , Renato Portugal , Franklin L. Marquezino

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 elaborate on a model of quantum random walk proposed by Hillery et. al., and Jeong et. al., which uses the multiports for quantum "coin tossing". The dynamics of this model is analyzed for the case when the multiports are arranged on the…

Quantum Physics · Physics 2016-09-08 Jozef Košík , Vladimír Bužek