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Related papers: Quantum random walks with decoherent coins

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We focus on a 2-period time-dependent quantum walk on the half line in this paper. The quantum walker launches at the edge of the half line in a localized superposition state and its time evolution is carried out with two unitary operations…

Quantum Physics · Physics 2020-08-28 Takuya Machida

Quantum random walks are shown to have non-intuitive dynamics, which makes them an attractive area of study for devising quantum algorithms for well-known classical problems as well as those arising in the field of quantum computing. In…

Quantum Physics · Physics 2007-12-11 K. Manouchehri , J. B. Wang

We perform a systematic study of the discrete time Quantum Walk on one dimension using Wigner functions, which are generalized to include the chirality (or coin) degree of freedom. In particular, we analyze the evolution of the negative…

Quantum Physics · Physics 2012-04-06 M. Hinarejos , M. C. Banuls , A. Perez

We study large time behavior of quantum walks (QW) with self-dependent coin. In particular, we show scattering and derive the reproducing formula for inverse scattering in the weak nonlinear regime. The proof is based on space-time estimate…

Mathematical Physics · Physics 2017-11-08 Masaya Maeda , Hironobu Sasaki , Etsuo Segawa , Akito Suzuki , Kanako Suzuki

The discrete-time quantum walk (QW) has been extensively and intensively investigated for the last decade, whose coin operator is defined by a unitary matrix. We extend the QW to a walk determined by a unitary matrix whose component is…

Quantum Physics · Physics 2015-05-05 Norio Konno

We implement the discrete-time quantum walk model using the continuous-time evolution of the Hamiltonian that includes both the shift and the coin generators. Based on the Trotter-Suzuki first-order approximation, we consider an…

Quantum Physics · Physics 2022-03-03 Jalil Khatibi Moqadam , Marcos Cesar de Oliveira

A number of recent studies have investigated the introduction of decoherence in quantum walks and the resulting transition to classical random walks. Interestingly, it has been shown that algorithmic properties of quantum walks with…

Quantum Physics · Physics 2016-01-19 Andrea Torsello , Luca Rossi

The dynamics of a one dimensional quantum walker on the lattice with two internal degrees of freedom, the coin states, is considered. The discrete time unitary dynamics is determined by the repeated action of a coin operator in U(2) on the…

Mathematical Physics · Physics 2010-04-26 Alain Joye , Marco Merkli

We introduce a variation of the discrete time quantum walk, the nonreversal quantum walk, which does not step back onto a position which it has just occupied. This allows us to simulate a dimer and we achieve it by introducing a new type of…

Quantum Physics · Physics 2014-06-27 T. J. Proctor , K. E. Barr , B. Hanson , S. Martiel , V. Pavlovic , A. Bullivant , V. M. Kendon

Temporal fluctuations in the Hadamard walk on circles are studied. A temporal standard deviation of probability that a quantum random walker is positive at a given site is introduced to manifest striking differences between quantum and…

Quantum Physics · Physics 2007-05-23 Norio Inui , Yoshinao Konishi , Norio Konno , Takahiro Soshi

In discrete-time quantum walk (DTQW) the walker's coin space entangles with the position space after the very first step of the evolution. This phenomenon may be exploited to obtain the value of the coin parameter $\theta$ by performing…

Quantum Physics · Physics 2019-07-10 Shivani Singh , C. M. Chandrashekar , Matteo G. A. Paris

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

The discrete time quantum walk which is a quantum counterpart of random walk plays important roles in the theory of quantum information theory. In the present paper, we focus on discrete time quantum walks viewed as quantization of random…

Quantum Physics · Physics 2013-12-13 Yusuke Ide , Norio Konno , Etsuo Segawa

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

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

We provide an explanation of recent experimental results of Xue et al., where full revivals in a time-dependent quantum walk model with a periodically changing coin are found. Using methods originally developed for "electric" walks with a…

Quantum Physics · Physics 2016-04-08 C. Cedzich , R. F. Werner

This work focuses on the study of quantum stochastic walks, which are a generalization of coherent, i. e. unitary quantum walks. Our main goal is to present a measure of a coherence of the walk. To this end, we utilize the asymptotic…

Quantum Physics · Physics 2018-03-21 Krzysztof Domino , Adam Glos , Mateusz Ostaszewski , Łukasz Pawela , Przemysław Sadowski

We report on a discrete-time quantum walk that uses the momentum of ultra-cold rubidium-87 atoms as the walk space and two internal atomic states as the coin degree of freedom. Each step of the walk consists of a coin toss (a microwave…

Quantum Physics · Physics 2019-04-26 Siamak Dadras , Alexander Gresch , Caspar Groiseau , Sandro Wimberger , Gil S. Summy

Multilayer network is a potent platform which paves a way to study the interactions among entities in various networks with multiple types of relationships. In this study, the dynamics of discrete-time quantum walk on a multilayer network…

Quantum Physics · Physics 2023-10-05 M. N. Jayakody , Priodyuti Pradhan , Dana Ben Porath , E. Cohen

The quantum walk is the quantum analogue of the well-known random walk, which forms the basis for models and applications in many realms of science. Its properties are markedly different from the classical counterpart and might lead to…