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Related papers: Quantum walk-based search and centrality

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We introduce a continuous-time quantum walk on an ultrametric space corresponding to the set of p-adic integers and compute its time-averaged probability distribution. It is shown that localization occurs for any location of the ultrametric…

Quantum Physics · Physics 2009-03-24 Norio Konno

Quantum walk is fundamental to designing many quantum algorithms. Here we consider the effects of quantum coherence and quantum entanglement for the quantum walk search on the complete bipartite graph. First, we numerically show the…

Quantum Physics · Physics 2023-10-03 Meng Li , Xian Shi

We solve an open problem by constructing quantum walks that not only detect but also find marked vertices in a graph. In the case when the marked set $M$ consists of a single vertex, the number of steps of the quantum walk is quadratically…

Quantum Physics · Physics 2016-03-01 Hari Krovi , Frédéric Magniez , Maris Ozols , Jérémie Roland

A quantum walk algorithm can detect the presence of a marked vertex on a graph quadratically faster than the corresponding random walk algorithm (Szegedy, FOCS 2004). However, quantum algorithms that actually find a marked element…

Quantum Physics · Physics 2019-03-19 Andris Ambainis , András Gilyén , Stacey Jeffery , Martins Kokainis

We study whether the probability distribution of a discrete quantum walk can get arbitrarily close to uniform, given that the walk starts with a uniform superposition of the outgoing arcs of some vertex. We establish a characterization of…

Combinatorics · Mathematics 2024-07-03 Hanmeng Zhan

In this paper, we analyze the application of the Multi-self-loop Lackadaisical Quantum Walk on the hypercube that uses partial phase inversion to search for multiple adjacent marked vertices. We evaluate the influence of the relative…

The spatial search problem aims to find a marked vertex of a finite graph using a dynamic with two constraints: (1) The walker has no compass and (2) the walker can check whether a vertex is marked only after reaching it. This problem is a…

Quantum Physics · Physics 2022-06-02 Hajime Tanaka , Mohamed Sabri , Renato Portugal

Network centrality has important implications well beyond its role in physical and information transport analysis; as such, various quantum walk-based algorithms have been proposed for measuring network vertex centrality. In this work, we…

Quantum Physics · Physics 2017-04-03 Josh A. Izaac , Xiang Zhan , Zhihao Bian , Kunkun Wang , ian Li , Jingbo B. Wang , Peng Xue

We investigate the behavior of coherence in scattering quantum walk search on complete graph under the condition that the total number of vertices of the graph is greatly larger than the marked number of vertices we are searching, $N \gg…

Quantum Physics · Physics 2020-03-19 Yun-Long Su , Si-Yuan Liu , Xiao-Hui Wang , Heng Fan , Wen-Li Yang

Quantum walks (QW) are of crucial importance in the development of quantum information processing algorithms. Recently, several quantum algorithms have been proposed to implement network analysis, in particular to rank the centrality of…

Quantum Physics · Physics 2021-01-04 Tong Wu , J. A. Izaac , Zi-Xi Li , Kai Wang , Zhao-Zhong Chen , Shining Zhu , J. B. Wang , Xiao-Song Ma

Spatial search is the problem of finding a marked vertex in a graph. A continuous-time quantum walk in the single-excitation subspace of an $n$ spin system solves the problem of spatial search by finding the marked vertex in $O(\sqrt{n})$…

Quantum Physics · Physics 2024-10-10 Dylan Lewis , Leonardo Banchi , Sougato Bose

Continuous-time quantum walks provide a natural framework to tackle the fundamental problem of finding a node among a set of marked nodes in a graph, known as spatial search. Whether spatial search by continuous-time quantum walk provides a…

Quantum Physics · Physics 2022-10-24 Simon Apers , Shantanav Chakraborty , Leonardo Novo , Jérémie Roland

A randomly walking quantum particle evolving by Schr\"odinger's equation searches for a unique marked vertex on the "simplex of complete graphs" in time $\Theta(N^{3/4})$. In this paper, we give a weighted version of this graph that…

Quantum Physics · Physics 2015-09-22 Thomas G. Wong

The lackadaisical quantum walk is a discrete-time, coined quantum walk on a graph with a weighted self-loop at each vertex. It uses a generalized Grover coin and the flip-flop shift, which makes it equivalent to Szegedy's quantum Markov…

Quantum Physics · Physics 2020-09-18 Mason L. Rhodes , Thomas G. Wong

Quantum walk has been successfully used to search for targets on graphs with vertices identified as the elements of a database. This spacial search on a two-dimensional periodic grid takes $\mathcal{O}\left(\sqrt{N\log N}\right)$ oracle…

Quantum Physics · Physics 2025-03-07 Pulak Ranjan Giri

Quantum walks underlie an important class of quantum computing algorithms, and represent promising approaches in various simulations and practical applications. Here we design stroboscopically monitored quantum walks and their subsequent…

Quantum Physics · Physics 2022-09-27 Quancheng Liu , David A. Kessler , Eli Barkai

The Scattering Quantum Random Walk scheme has found success as a basis for search algorithms on highly symmetric graph structures. In this paper we examine its effectiveness at locating a specially marked vertex on square grid graphs,…

Quantum Physics · Physics 2019-01-23 Daniel Koch

In this paper, we consider a continuous-time quantum walk based search algorithm. We introduce equitable partition of the graph and perfect state transfer on it. By these two methods, we can calculate the success probability and the finding…

Quantum Physics · Physics 2022-09-19 Yusuke Ide , Akihiro Narimatsu

The lackadaisical quantum walk is a quantum analogue of the lazy random walk obtained by adding a self-loop to each vertex in the graph. We analytically prove that lackadaisical quantum walks can find a unique marked vertex on any regular…

Quantum Physics · Physics 2022-02-01 Peter Høyer , Zhan Yu

The problem of finding a marked node in a graph can be solved by the spatial search algorithm based on continuous-time quantum walks (CTQW). However, this algorithm is known to run in optimal time only for a handful of graphs. In this work,…

Quantum Physics · Physics 2016-03-23 Shantanav Chakraborty , Leonardo Novo , Andris Ambainis , Yasser Omar