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Related papers: Continuous Limit of Discrete Quantum Walks

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In this paper, we study the recurrence of Open Quantum Walks induced by finite-dimensional coins on the line ($\mathbb{Z}$) and on the grid ($\mathbb{Z}^2$). Two versions are considered: discrete-time open quantum walks (OQW) and…

Quantum Physics · Physics 2026-03-23 Newton Loebens

The dynamics of a discrete-time quantum walk (DTQW) can be realized within a purely classical interacting particle system composed of some boxes and a large but finite number of balls, and can, in principle, be implemented in a tabletop…

Quantum Physics · Physics 2026-03-03 Surajit Saha

We present a detailed analysis of continuous time quantum walks (CTQW) with both position and transition defects defined at a single point in the line. Analytical solutions of both traveling waves or bound states are obtained, which provide…

Quantum Physics · Physics 2015-09-08 Zhi-Jian Li , J. B. Wang

In discrete time, coined quantum walks, the coin degrees of freedom offer the potential for a wider range of controls over the evolution of the walk than are available in the continuous time quantum walk. This paper explores some of the…

Quantum Physics · Physics 2009-11-10 Ben Tregenna , Will Flanagan , Rik Maile , Viv Kendon

We show how to search N items arranged on a $\sqrt{N}\times\sqrt{N}$ grid in time $O(\sqrt N \log N)$, using a discrete time quantum walk. This result for the first time exhibits a significant difference between discrete time and continuous…

Quantum Physics · Physics 2007-05-23 Andris Ambainis , Julia Kempe , Alexander Rivosh

Quantum walks (QWs) describe particles evolving coherently on a lattice. The internal degree of freedom corresponds to a Hilbert space, called coin system. We consider QWs on Cayley graphs of some group $G$. In the literature,…

Continuous-time quantum walks (CTQWs) play a crucial role in quantum computing, especially for designing quantum algorithms. However, how to efficiently implement CTQWs is a challenging issue. In this paper, we study implementation of CTQWs…

Quantum Physics · Physics 2024-11-19 Zhaoyang Chen , Guanzhong Li , Lvzhou Li

In recent years, several properties and recurrence criteria of discrete-time open quantum walks (OQWs) have been presented. Recently, Pellegrini introduced continuous-time open quantum walks (CTOQWs) as continuous-time natural limits of…

Quantum Physics · Physics 2023-06-01 Newton Loebens

The quantum circuit model is the most commonly used model for implementing quantum computers and quantum neural networks whose essential tasks are to realize certain unitary operations. The circuit model usually implements a desired unitary…

Quantum Physics · Physics 2023-04-14 Jia-Yi Lin , Xin-Yu Li , Yu-Hao Shao , Wei Wang , Shengjun Wu

Quantum walks are referred to as quantum analogs to random walks in mathematics. They have been studied as quantum algorithms in quantum information for quantum computers. There are two types of quantum walks. One is the discrete-time…

Quantum Physics · Physics 2024-06-26 Takuya Machida

Quantum walks have proven to be a universal model for quantum computation and to provide speed-up in certain quantum algorithms. The discrete-time quantum walk (DTQW) model, among others, is one of the most suitable candidates for circuit…

Quantum Physics · Physics 2024-04-10 Luca Razzoli , Gabriele Cenedese , Maria Bondani , Giuliano Benenti

We consider a discrete-time quantum walk $W_{t,\kappa}$ at time $t$ on a graph with joined half lines $\mathbb{J}_\kappa$, which is composed of $\kappa$ half lines with the same origin. Our analysis is based on a reduction of the walk on a…

Quantum Physics · Physics 2012-01-12 Kota Chisaki , Norio Konno , Etsuo Segawa

This paper is devoted to the study of continuous-time processes known as continuous-time open quantum walks (CTOQWs). A CTOQW represents the evolution of a quantum particle constrained to move on a discrete graph, but also has internal…

Probability · Mathematics 2018-03-12 Ivan Bardet , Hugo Bringuier , Yan Pautrat , Clement Pellegrini

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a…

Quantum Physics · Physics 2012-10-01 Salvador E. Venegas-Andraca

Continuous time quantum walks (CTQW) do not necessarily perform better than their classical counterparts, the continuous time random walks (CTRW). For one special graph, where a recent analysis showed that in a particular direction of…

Quantum Physics · Physics 2009-11-10 Oliver Muelken , Alexander Blumen

In this dissertation we demonstrate that the continuous-time quantum walk models remain powerful for nontrivial graph structures. We consider two aspects of this problem. First, it is known that the standard Continuous-Time Quantum Walk…

Quantum Physics · Physics 2021-09-28 Adam Glos

We identify a key difference between quantum search by discrete- and continuous-time quantum walks: a discrete-time walk typically performs one walk step per oracle query, whereas a continuous-time walk can effectively perform multiple walk…

Quantum Physics · Physics 2015-08-24 Thomas G. Wong , Andris Ambainis

The quantum random walk has been much studied recently, largely due to its highly nonclassical behavior. In this paper, we study one possible route to classical behavior for the discrete quantum walk on the line: the presence of decoherence…

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

The quantum circuit model is the most commonly used model for implementing quantum computers and quantum neural networks whose essential tasks are to realize certain unitary operations. Here we propose an alternative approach; we use a…

Quantum Physics · Physics 2023-04-14 Jia-Yi Lin , Xin-Yu Li , Yu-Hao Shao , Wei Wang , Shengjun Wu

Quantum walk (QW) is the quantum analog of the random walk. QW is an integral part of the development of numerous quantum algorithms. Hence, an in-depth understanding of QW helps us to grasp the quantum algorithms. We revisit the…

Quantum Physics · Physics 2021-02-16 Mahesh N. Jayakody , Chandrakala Meena , Priodyuti Pradhan