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We perform a finite-time scaling analysis over the detrapping point of a three-state quantum walk on the line. The coin operator is parameterized by $\rho$ that controls the wavepacket spreading velocity. The input state prepared at the…

Quantum Physics · Physics 2021-11-15 P. R. N. Falcão , A. R. C. Buarque , W. S. Dias , G. M. A. Almeida , M. L. Lyra

Quantum walks provide a framework for understanding and designing quantum algorithms that is both intuitive and universal. To leverage the computational power of these walks, it is important to be able to programmably modify the graph a…

Quantum Physics · Physics 2022-09-07 Aaron W. Young , William J. Eckner , Nathan Schine , Andrew M. Childs , Adam M. Kaufman

Continuous-time quantum walk is one of the alternative approaches to quantum computation, where a universal set of quantum gates can be achieved by scattering a quantum walker on some specially-designed structures embedded in a sparse graph…

Quantum Physics · Physics 2023-05-11 Fan Wang , Bin Cheng , Zi-Wei Cui , Man-Hong Yung

A new model maps a quantum random walk described by a Hadamard operator to a particular case of a birth and death process. The model is represented by a 2D Markov chain with a stochastic matrix, i.e., all the transition rates are positive,…

Quantum Physics · Physics 2021-04-13 Arie Bar-Haim

In this paper, a study on discrete-time coined quantum walks on the line is presented. Clear mathematical foundations are still lacking for this quantum walk model. As a step towards this objective, the following question is being…

Quantum Physics · Physics 2013-01-01 Marcos Villagra , Masaki Nakanishi , Shigeru Yamashita , Yasuhiko Nakashima

A connection between the asymptotic behavior of the open quantum walk and the spectrum of a generalized quantum coins is studied. For the case of simultaneously diagonalizable transition operators an exact expression for probability…

Quantum Physics · Physics 2014-02-07 I. Sinayskiy , F. Petruccione

We demonstrate a quantum walk with time-dependent coin bias. With this technique we realize an experimental single-photon one-dimensional quantum walk with a linearly-ramped time-dependent coin flip operation and thereby demonstrate two…

Quantum Physics · Physics 2015-08-11 Peng Xue , Rong Zhang , Hao Qin , Xiang Zhan , Zhihao Bian , Jian Li , Barry C. Sanders

We study a class of symmetric quantum walks on Hamming graphs, where the distance between vertices specifies the transition probability. A special model is the simple quantum walk on the hypercube, which has been discussed in the…

Quantum Physics · Physics 2026-03-25 Robert Griffiths , Shuhei Mano

The evolution of a many-particle system on a one-dimensional lattice, subjected to a quantum walk can cause spatial entanglement in the lattice position, which can be exploited for quantum information/communication purposes. We demonstrate…

Quantum Physics · Physics 2010-05-21 Sandeep K. Goyal , C. M. Chandrashekar

We generalize the discrete quantum walk on the line using a time dependent unitary coin operator. We find an analytical relation between the long-time behaviors of the standard deviation and the coin operator. Selecting the coin time…

Quantum Physics · Physics 2015-05-13 Alejandro Romanelli

We propose a scheme to implement the one-dimensional coined quantum walk with electrons transported through a two-dimensional network of spintronic semiconductor quantum rings. The coin degree of freedom is represented by the spin of the…

Mesoscale and Nanoscale Physics · Physics 2009-07-30 Orsolya Kálmán , Tamás Kiss , Péter Földi

Lazy quantum walks were presented by Andrew M. Childs to prove that the continuous-time quantum walk is a limit of the discrete-time quantum walk [Commun.Math.Phys.294,581-603(2010)]. In this paper, we discuss properties of lazy quantum…

Quantum Physics · Physics 2015-09-01 Dan Li , Michael Mc Gettrick , Wei-Wei Zhang , Ke-Jia Zhang

When random walks on a square lattice are biased horizontally to move solely to the right, the probability distribution of their algebraic area can be exactly obtained. We explicitly map this biased classical random system on a non…

Statistical Mechanics · Physics 2015-06-17 Sergey Matveenko , Stephane Ouvry

Currently there are three major paradigms of quantum computation, the gate model, annealing, and walks on graphs. The gate model and quantum walks on graphs are universal computation models, while annealing plays within a specific subset of…

Quantum Physics · Physics 2021-04-16 Clark Alexander

Existence of the eigenvalues of the discrete-time quantum walks is deeply related to localization of the walks. We revealed the distributions of the eigenvalues given by the splitted generating function method (the SGF method) of the…

Spectral Theory · Mathematics 2020-02-19 Shimpei Endo , Takako Endo , Takashi Komatsu , Norio Konno

The parametric maximum likelihood estimation problem is addressed in the context of quantum walk theory for quantum walks on the lattice of integers. A coin action is presented, with the real parameter $\theta$ to be estimated identified…

Quantum Physics · Physics 2023-05-31 Demosthenes Ellinas , Peter D. Jarvis , Matthew Pearce

There are presently two models for quantum walks on graphs. The "coined" walk uses discrete time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the…

Quantum Physics · Physics 2009-11-10 Mark Hillery , Janos Bergou , Edgar Feldman

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

Quantum walks are the quantum-mechanical analog of random walks, in which a quantum `walker' evolves between initial and final states by traversing the edges of a graph, either in discrete steps from node to node or via continuous evolution…

Quantum Physics · Physics 2015-05-19 Michael S. Underwood , David L. Feder

We study quantum algorithms for spatial search on finite dimensional grids. Patel et al. and Falk have proposed algorithms based on a quantum walk without a coin, with different operators applied at even and odd steps. Until now, such…

Quantum Physics · Physics 2015-10-14 Andris Ambainis , Renato Portugal , Nikolay Nahimov